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Archive for the ‘Genetic Engineering’ Category

Genetic Engineering in Agriculture | Union of Concerned …

Thursday, August 4th, 2016

Yes. We understand the potential benefits of the technology, and support continued advances in molecular biology, the underlying science. But we are critics of the business models and regulatory systems that have characterized early deployment of these technologies. GE has proved valuable in some areas (as in the contained use of engineered bacteria in pharmaceutical development), and some GE applications could turn out to play a useful role in food production.

Thus far, however, GE applications in agriculture have only made the problems of industrial monocropping worse. Rather than supporting a more sustainable agriculture and food system with broad societal benefits, the technology has been employed in ways that reinforce problematic industrial approaches to agriculture. Policy decisions about the use of GE have too often been driven by biotech industry public relations campaigns, rather than by what science tells us about the most cost-effective ways to produce abundant food and preserve the health of our farmland.

These are a few things policy makers should do to best serve the public interest:

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Articles about Genetic Engineering – latimes

Thursday, August 4th, 2016

NATIONAL

October 30, 2013 | By Maria L. La Ganga

SEATTLE - A year after Proposition 37 narrowly failed in California, the labeling of genetically engineered foods is back on the ballot in Washington state, complete with a lawsuit by the state attorney general, a barrage of ads and a stark example of money's effect on politics. I-522, as it is called, officially became the most expensive initiative battle in Washington history this week, with a not-so-Washington twist. Out-of-state money is driving the debate. Of the $33 million raised to fight the labeling effort, about $10,000 came from donors within the state - making up just 0.03% of the "no" campaign war chest.

OPINION

August 30, 2013 | By Henry I. Miller

Americans might soon need to get used to apple or grape juice as their breakfast drink of choice - unless, that is, they're willing to pay exorbitant prices for orange juice. Or maybe scientists, plant breeders and farmers will manage to save the day, using two critical but often-disparaged technologies: chemical pesticides in the short run and genetic engineering in the longer term. The pestilence that is devastating Florida citrus is a disease called citrus greening. It is caused by a bacterium, Candidatus Liberibacter asiaticus , which is spread by small insects called psyllids.

NEWS

June 17, 2013 | By Karin Klein

There's a dearth of evidence that genetically engineered food is dangerous to human health - but that doesn't mean consumers are wrong to have concerns about its effect on the environment and on non-bioengineered crops. U.S. agribusiness has rushed to embrace the GMO (for genetically modified organism, though genetically engineered is a more accurate term) possibilities, with almost all of our corn, soy and canola now featuring genes that have been tinkered with, usually to make them resistant to certain herbicides.

OPINION

May 24, 2013 | By The Times editorial board

The movement to force the labeling of genetically engineered food is gaining momentum. In November 2012, an initiative to require the labels in California was on the ballot; it was defeated. Now, federal legislation carried by Sen. Barbara Boxer (D-Calif.) would mandate labeling most bioengineered food nationwide. Yet the movement's argument is weakened by the lack of evidence that inserting fragments of DNA into crops harms our health. Pro-labeling activists - who also tend to be anti-Monsanto activists - point to polls finding that most Americans want the information labeled.

SCIENCE

March 23, 2013 | By Rosie Mestel, Los Angeles Times

When is a fish not a fish but a drug? When government regulators take old laws and twist themselves into knots trying to apply them to new technology. In the emotionally charged battle over the safety and appropriateness of genetically modified foods, people on both sides agree that the way the government oversees genetically modified plants and animals is patchy, inconsistent and at times just plain bizarre. Soon, analysts say, the system may be stretched to the breaking point.

NEWS

March 20, 2013 | By Monte Morin

Researchers at UCLA have genetically engineered tomatoes that, when fed to mice, mimic the beneficial qualities of good cholesterol, according to a new study. In a paper published Tuesday in the Journal of Lipid Research, authors used bacteria to insert genes into the cells of tomato plants, so that they would produce a peptide that mimics the actions of HDL, or "good" cholesterol. Later generations of those genetically engineered tomatoes were frozen, ground up and then fed to female mice who were themselves bred to be highly susceptible to LDL, or "bad" cholesterol.

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What Is Genetic Engineering?

Thursday, August 4th, 2016

What is Genetic Engineering?

Written by: Dr. Ricarda Steinbrecher WEN Trust, July 1998

Synthesis/Regeneration: A Magazine of Green Social Thought, Vol. 18 (Winter 1999), pp. 9-12 [Note: For technical reasons, the graphics accompanying the orginal article have not been reproduced here.]

We find it mixed in our food on the shelves in the supermarket--genetically engineered soybeans and maize. We find it growing in a plot down the lane, test field release sites with genetically engineered rape seed, sugar beet, wheat, potato, strawberries and more. There has been no warning and no consultation.

It is variously known as genetic engineering, genetic modification or genetic manipulation. All three terms mean the same thing, the reshuffling of genes usually from one species to another; existing examples include: from fish to tomato or from human to pig. Genetic engineering (GE) comes under the broad heading of biotechnology.

But how does it work? If you want to understand genetic engineering it is best to start with some basic biology.

What is a cell? A cell is the smallest living unit, the basic structural and functional unit of all living matter, whether that is a plant, an animal or a fungus.Some organisms such as amoebae, bacteria, some algae and fungi are single-celled - the entire organism is contained in just one cell. Humans are quite different and are made up of approximately 3 million cells -(3,000,000,000,000 cells). Cells can take many shapes depending on their function, but commonly they will look like a brick with rounded comers or an angular blob - a building block.Cells are stacked together to make up tissues, organs or structures (brain, liver, bones, skin, leaves, fruit etc.).

In an organism, cells depend on each other to perform various functions and tasks; some cells will produce enzymes, others will store sugars or fat; different cells again will build the skeleton or be in charge of communication like nerve cells; others are there for defence, such as white blood cells or stinging cells in jelly fish and plants. In order to be a fully functional part of the whole, most cells have got the same information and resources and the same basic equipment.

A cell belonging to higher organisms (e.g. plant or animal) is composed of: a cell MEMBRANE enclosing the whole cell. (Plant cells have an additional cell wall for structural reinforcement.) many ORGANELLES, which are functional components equivalent to the organs in the body of an animal e.g. for digestion, storage, excretion. a NUCLEUS, the command centre of the cell. It contains all the vital information needed by the cell or the whole organism to function, grow and reproduce. This information is stored in the form of a genetic code on the chromosomes, which are situated inside the nucleus.

Proteins are the basic building materials of a cell, made by the cell itself. Looking at them in close-up they consist of a chain of amino-acids, small specific building blocks that easily link up. Though the basic structure of proteins is linear, they are usually folded and folded again into complex structures. Different proteins have different functions. They can be transport molecules (e.g. oxygen binding haemoglobin of the red blood cells); they can be antibodies, messengers, enzymes (e.g. digestion enzymes) or hormones (e.g. growth hormones or insulin). Another group is the structural proteins that form boundaries and provide movement, elasticity and the ability to contract. Muscle fibres, for example, are mainly made of proteins. Proteins are thus crucial in the formation of cells and in giving cells the capacity to function properly.

Chromosomes means "coloured bodies" (they can be seen under the light microscope, using a particular stain). They look like bundled up knots and loops of a long thin thread. Chromosomes are the storage place for all genetic - that is hereditary - information. This information is written along the thin thread, called DNA. "DNA" is an abbreviation for deoxyribo nucleic acid, a specific acidic material that can be found in the nucleus. The genetic information is written in the form of a code, almost like a music tape. To ensure the thread and the information are stable and safe, a twisted double stranded thread is used - the famous double helix. When a cell multiplies it will also copy all the DNA and pass it on to the daughter cell.

The totality of the genetic information of an organism is called genome. Cells of humans, for example, possess two sets of 23 different chromosomes, one set from the mother and the other from -the father. The DNA of each human cell corresponds to 2 meters of DNA if it is stretched out and it is thus crucial to organise the DNA in chromosomes, so as to avoid knots, tangles and breakages. The length of DNA contained in the human body is approximately 60,000,000,000 kilometres. This is equivalent to the distance to the moon and back 8000 times!

The information contained on the chromo-somes in the DNA is written and coded in such a way that it can be understood by almost all living species on earth. It is thus termed the universal code of life. In this coding system, cells need only four symbols (called nucleotides) to spell out all the instructions of how to make any protein. Nucleotides are the units DNA is composed of and their individual names are commonly abbreviated to the letters A, C G and T These letters are arranged in 3-letter words which in turn code for a particular amino acid - as shown in the flow diagram 1. The information for how any cell is structured or how it functions is all encoded in single and distinct genes. A Gene is a certain segment (length) of DNA with specific instructions for the production of commonly one specific protein. The coding sequence of a gene is, on average about 1000 letters long. Genes code for example for insulin, digestive enzymes, blood clotting proteins, or pigments.

How does a cell know when to produce which protein and how much of it? In front of each gene there is a stretch of DNA that contains the regulatory elements for that specific gene, most of which is known as the promoter. It functions like a "control tower," constantly holding a "flag" up for the gene it controls. Take insulin production (which we produce to enable the burning of the blood sugar). When a message arrives in the form of a molecule that says, 'more insulin", the insulin control tower will signal the location of the insulin gene and say "over here". The message molecule will "dock in" and thus activate a "switch" to start the whole process of gene expression.

How does the information contained in the DNA get turned into a protein at the right time? As shown in picture 2, each gene consists of 3 main components: a "control tower" (promoter), an information block and a polyA signal element. If there is not enough of a specific protein present in the cell, a message will be sent into the nucleus to find the relevant gene. If the control tower recognises the message as valid it will open the "gate" to the information block. Immediately the information is copied - or transcribed - into a threadlike molecule, called RNA. RNA is very similar to DNA, except it is single stranded. After the copy is made, a string of up to 200 "A"-type nucleotides - a polyA tail - is added to its end (picture 2). This process is called poly-adenylation and is initiated by a polyA signal located towards the end of the gene. A polyA tail is thought to stabilise the RNA message against degradation for a limited time. Now the RNA copies of the gene leave the nucleus and get distributed within the cell to little work units that translate the information into proteins.

No cell will ever make use of all the information coded in its DNA. Cells divide the work up amongst one other - they specialise. Brain cells will not produce insulin, liver cells will not produce saliva, nor will skin cells start producing bone. If they did, our bodies could be chaos!

The same is true for plants: root cells will not produce the green chlorophyll, nor will the leaves produce pollen or nectar. Furthermore, expression is age dependent: young shoots will not express any genes to do with fruit ripening, while old people will not usually start developing another set of teeth (exceptions have been known).

All in all, gene regulation is very specific to the environment in which the cell finds itself and is also linked to the developmental stages of an organism. So f I want the leaves of poppy plants to produce the red colour of the flower petals I will not be able to do so by traditional breeding methods, despite the fact that leaf ells will have all the genetic information necessary. There is a block that prevents he leaves from going red. This block may be caused by two things: The "red" gene has been permanently shut down and bundled up thoroughly in all leaf cells. Thus the information cannot be accessed any more. The leaf cells do not need the colour red and thus do not request RNA copies of this information. Therefore no message molecule is docking at the "red" control tower to activate the gene.

Of course - you might have guessed - there is a trick to fool the plant and make it turn red against its own will. We can bring the red gene in like a Trojan horse, hidden behind the control tower of a different gene. But for this we need to cut the genes up and glue them together in a different form. This is where breeding ends and genetic engineering begins.

BREEDING is the natural process of sexual reproduction within the same species. The hereditary information of both parents is combined and passed on to the offspring. In this process the same sections of DNA can be exchanged between the same chromosomes, but genes will always remain at their very own and precise position and order on the chromosomes. A gene will thus always be surrounded by the same DNA unless mutations or accidents occur. Species that are closely related might be able to interbreed, like a donkey and a horse, but their offspring will usually be infertile (e.g. mule). This is a natural safety devise, preventing the mixing of genes that might not be compatible and to secure the survival of the species.

GENETIC ENGINEERING

Genetic engineering (GE) is used to take genes and segments of DNA from one species, e.g. fish, and put them into another species, e.g. tomato. To do so, GE provides a set of techniques to cut DNA either randomly or at a number of specific sites. Once isolated one can study the different segments of DNA, multiply them up and splice them (stick them) next to any other DNA of another cell or organism. GE makes it possible to break through the species barrier and to shuffle information between completely unrelated species; for example, to splice the anti-freeze gene from flounder into tomatoes or strawberries, an insect-killing toxin gene from bacteria into maize, cotton or rape seed, or genes from humans into pig.

Yet there is a problem - a fish gene will not work in tomato unless I give it a promoter with a "flag" the tomato cells will recognise. Such a control sequence should either be a tomato sequence or something similar. Most companies and scientists do a shortcut here and don't even bother to look for an appropriate tomato promoter as it would take years to understand how the cell's internal communication and regulation works. In order to avoid long testing and adjusting, most genetic engineering of plants is done with viral promoters. Viruses - as you will be aware - are very active. Nothing, or almost nothing, will stop them once they have found a new victim or rather host. They integrate their genetic information into the DNA of a host cell (such as one of your own), multiply, infect the next cells and multiply. This is possible because viruses have evolved very powerful promoters which command the host cell to constantly read the viral genes and produce viral proteins. Simply by taking a control element (promoter) from a plant virus and sticking it in front of the information block of the fish gene, you can get this combined virus/fish gene (known as a "construct') to work wherever and whenever you want in a plant.

This might sound great, the drawback though is that it can't be stopped either, it can't be switched off. The plant no longer has a say in the expression of the new gene, even when the constant involuntary production of the "new" product is weakening the plant's defences or growth.

And furthermore, the theory doesn't hold up with reality. Often, for no apparent reason, the new gene only works for a limited amount of time and then "falls silent". But there is no way to know in advance if this will happen.

Though often hailed as a precise method, the final stage of placing the new gene into a receiving higher organism is rather crude, seriously lacking both precision and predictability. The "new" gene can end up anywhere, next to any gene or even within another gene, disturbing its function or regulation. If the "new" gene gets into the "quiet" non-expressed areas of the cell's DNA, it is likely to interfere with the regulation of gene expression of the whole region. It could potentially cause genes in the "quiet" DNA to become active.

Often genetic engineering will not only use the information of one gene and put it behind the promoter of another gene, but will also take bits and pieces from other genes and other species. Although this is aimed to benefit the expression and function of the "new" gene it also causes more interference and enhances the risks of unpredictable effects.

How to get the gene into the other cell.

There are different ways to get a gene from A to B or to transform a plant with a "new" gene. A VECTOR is something that can carry the gene into the host, or rather into the nucleus of a host cell. Vectors are commonly bacterial plasmids (see below and next page) or viruses (a). Another method is the "SHOTGUN TECHNIQUE" also known as "bio-ballistics," which blindly shoots masses of tiny gold particles coated with the gene into a plate of plant cells, hoping to land a hit somewhere in the cell's DNA (b).

What is a plasmid?

PLASMIDS can be found in many bacteria and are small rings of DNA with a limited number of genes. Plasmids are not essential for the survival of bacteria but can make life a lot easier for them. Whilst all bacteria - no matter which species - will have their bacterial chromosome with all the crucial hereditary information of how to survive and multiply, they invented a tool to exchange information rapidly. If one likens the chromosome to a bookshelf with manuals and handbooks, and a single gene to a recipe or a specific building instruction, a plasmid,could be seen as a pamphlet. Plasmids self-replicate and are thus easily reproduced and passed around. Plasmids often contain genes for antibiotic resistance. This type of information which can easily be passed on, can be crucial to bacterial strains which are under attack by drugs and is indeed a major reason for the quick spread of antibiotic resistance.

Working with plasmids.

Plasmids are relatively small, replicate very quickly and are thus easy to study and to manipulate. It is easy to determine the sequence of its DNA, that is, to find out the sequence of the letters (A, C, G and 1) and number them. Certain letter combinations -such as CAATTG - are easy to cut with the help of specific enzymes (see proteins). Ilese cutting enzymes, called restriction enzymes, are part of the Genetic Engineering "tool-kit" of biochemists. So if I want to splice a gene from fish into a plasmid, I have to take the following steps: I place a large number of a known plasmid in a little test tube and add a specific enzyme that will cut the plasmid at only one site. After an hour I stop the digest, purify the cut plasmid DNA and mix it with copies of the fish gene; after some time the fish gene places itself into the cut ring of the plasmid. I quickly add some "glue" from my "tool-kit" - an enzyme called ligase - and place the mended plasmids back into bacteria, leaving them to grow and multiply. But how do I know which bacteria will have my precious plasmid? For this reason I need MARKER GENES, such as antibiotic resistance genes. So I make sure my plasmid has a marker gene before I splice my fish gene into it. If thA I plasmid is marked with a gene antibiotic resistance I can now add specific antibiotic to the food supply of the bacteria. All those which do not have the plasmid will die, and all those that do have the plasmid will multiply.

Unanswered Questions and Inherent Uncertainties

What's wrong with Genetic Engineering ?

Genetic Engineering is a test tube science and is prematurely applied in food production. A gene studied in a test tube can only tell what this gene does and how it behaves in that particular test tube. It cannot tell us what its role and behaviour are in the organism it came from or what it might do if we place it into a completely different species. Genes for the colour red placed into petunia flowers not only changed the colour of the petals but also decreased fertility and altered the growth of the roots and leaves. Salmon genetically engineered with a growth hormone gene not only grew too big too fast but also turned green. These are unpredictable side effects, scientifically termed pleiotropic effects.

We also know very little about what a gene (or for that matter any of its DNA sequence) might trigger or interrupt depending on where it got inserted into the new host (plant or animal). These are open questions around positional effects. And what about gene silencing and gene instability? How do we know that a genetically engineered food plant will not produce new toxins and allergenic substances or increase the level of dormant toxins and allergens? How about the nutritional value? And what are the effects on the environment and on wild life? All these questions are important questions yet they remain unanswered. Until we have an answer to all of these, genetic engineering should be kept to the test tubes. Biotechnology married to corporations tends to ignore the precautionary principle but it also igpores some basic scientific principles.

What you can do:

Avoid genetically engineered (GE) food, currently in products containing soya and maize.

Buy organic products - look for the Soil Association label.

Tell your MP and the Minister of the Environment you object to GE crops being released on test sites in your area -or any area you care about. Ask your MP or the Department of Environment, Transport and the Regions (DETR) for details from the Public Register of GMOs (genetically modified organisms). DETR phone: 0171-890 5275.

Copy this briefing and give it to a neighbour /friend.

Contact your local paper; write a letter to the editor.

Demand clear choice and non-GE products from your supermarket (addresses of head offices and sample letter available from WEN).

Read up on the issue. Get WEN's Campaign Pack on Genetic Engineering (out in August, L2).

Join a local environmental group and campaign against GE crops and GE food.

Support WEN's Test Tube Harvest Campaign (cheques payable to: 'WEN- Test Tube Harvest').

Join the Women's Environmental Network.

Contact the Test Tube Harvest Campaign for further information.

Further contact: Genetic Engineering Network (GEN) -also runs email list. Phone: 0181 - 374 9516

----------------

The Women's Environmental Network Trust is a registered charity, educating, informing and empowering women who care about the environment. The WEN Trust Information Department answers enquiries and produces briefings, papers and other information related to women and the environment. For further details contact: Information Co-ordinator,WEN, 87 Worship Street, London EC2A 2BE, UK. Phone: (+44) 171-247 3327. Fax: (+44) 171-247 4740. Email: WENUK@gn.apc.org.

Prepared in co-operation with the Genetic Engineering Network, UK.

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Genetic Engineering – regentsprep.org

Thursday, August 4th, 2016

Vocabulary: selective breeding, recombinant DNA, artificial selection, inbreeding, hybridization, genetic engineering, restriction enzyme, cloning, genetic mapping, Human Genome Project

Genetic Engineering Throughout recorded history, humans have used selective breeding and other methods to produce organisms with desirable traits. Our current understanding of genetics and heredity allows for the manipulation of genes and the development of new combinations of traits and new varieties of organisms. This includes various aspects of DNA technology, including recombinant DNA technology. Scientists have also developed many ways of determining the genetic makeup of different organisms, including humans.

Selective Breeding For thousands of years new varieties of cultivated plants and domestic animals have resulted from selective breeding for particular traits. Some selective breeding techniques include artificial selection, where individuals with desirable traits are mated to produce offspring with those traits. A variation of this process traditionally used in agriculture is inbreeding, where the offspring produced by artificial selection are mated with one another to reinforce those desirable traits. Hybridization is a special case of selective breeding. This involves crossing two individuals with different desirable traits to produce offspring with a combination of both desirable traits. An example of this are Santa Gertrudis cattle, which were developed by breeding English shorthorn cattle, which provided for good beef, but lacked heat resistance, with Brahman cattle from India which were highly resistant to heat and humidity. The Santa Gertrudis breed of cattle has excellent beef, and thrives in hot, humid environments.

An Example of Selective Breeding

Brahman cattle: Good resistance to heat but poor beef.

English shorthorn cattle: Good beef but poor heat resistance.

Santa Gertrudis cattle: Formed by crossing Brahman and English shorthorns; has good heat resistance and beef.

Genetic Engineering In recent years new varieties of farm plants and animals have been engineered bymanipulating their genetic instructions to produce new characteristics. This technology is known as genetic engineering or recombinant DNA technology. Different enzymes can be used to cut, copy (clone), and move segments of DNA. An important category of enzyme used to cut a section of a gene and its DNA from an organism is known as a restriction enzyme. When this piece of DNA, which has been cut out of one organism, is placed in another organism, that section of gene will express the characteristics that were expressed by this gene in the organism it was taken from.

An Example of Genetic Engineering

Knowledge of genetics, including genetic engineering, is making possible new fields of health care. Genetic engineering is being used to engineer many new types of more efficient plants and animals, as well as provide chemicals needed for human health care. It may be possible to use aspect of genetic engineering to correct some human health defects. Some examples of chemicals being mass produced by human genes in bacteria include insulin, human growth hormone, and interferon. Substances from genetically engineered organisms have reduced the cost and side effects of replacing missing human body chemicals. While genetic engineering technology has many practical benefits, its use has also raised many legitimate ethical concerns.

Other Genetic Technologies Cloning involves producing a group of genetically identical offspring from the cells of an organism. This technique may greatly increase agricultural productivity. Plants and animals with desirable qualities can be rapidly produced from the cells of a single organism.

Genetic mapping, which is the location of specific genes inside the chromosomes of cells makes it possible to detect, and perhaps in the future correct defective genes that may lead to poor health. The human genome project has involved the mapping of the major genes influencing human traits, thus allowing humans to know the basic framework of their genetic code

Knowledge of genetics is making possible new fields of health care. Genetic mapping in combination with genetic engineering and other genetic technologies may make it possible to correct defective genes that may lead to poor health.

There are many ethical concerns to these advanced genetic technologies, including possible problems associated with the cloning of humans. Another down side to genetic mapping technologies it is possible that some organizations may use this genetic information against individuals.

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Genetic Engineering – Clackamas Community College

Thursday, August 4th, 2016

The mutations we've been discussing occur in a seemingly random manner by various mutagens. Mutation can also be caused in a very systematic way by viruses. Viruses can enter a host cell and then alter the DNA of the host cell by clipping it open and inserting new segments that will code for the viral protein, and they can do that by using the host cell's replication, transcription and translation mechanisms to create that viral protein.

This scenario is also related to the field known popularly as genetic engineering. Basically, it involves altering the DNA in a simple organism such as a bacterium in order to get the bacteria to produce a protein that it ordinarily would not produce, and this is done by snipping open a section of the bacterial DNA and inserting a gene from another organism. The technique is called gene splicing and it is often accomplished by inserting the new gene in a virus and then infecting the bacteria with the virus.

Here is one mechanism by which this can occur. Certain enzymes can open up the DNA sequence by breaking or hydrolyzing the phosphor ester bond in the DNA backbone.

In the lesson on proteins, I mentioned a disorder called diabetes, in which the messenger protein, insulin, is defective. Early treatment for this disease involved injecting insulin into patients in order to enable their cells to take up glucose. One problem with this treatment was that the only insulin available at a reasonable cost was insulin from cows. This insulin was slightly different and therefore not as effective as human insulin; moreover, some diabetics had what amounted to an allergic reaction to the foreign protein. In timet, genetic engineers were able to insert the gene for human insulin into a common bacterium called E. coli. When this bacterium was then grown in cultures, it produced vast quantities of human insulin which could be isolated fairly easily in pure form, for use by diabetics. Moreover, the human insulin was much cheaper when produced in this way than was the insulin from cows.

Another protein produced in this way is the protein interferon. When it was originally discovered, it was thought to be a potent cure for cancer and highly effective at preventing viral infection, and perhaps it might even be the long sought cure for the common cold. Unfortunately, it was incredibly expensive to isolate and available only in minute quantities. Not only was it impractical to use on a wide scale, it was not possible to do meaningful research with it, because such small amounts were available. A great deal of effort was expended to genetically alter bacteria to produce interferon. Effort which was eventually successful. Unfortunately, when sufficient quantities of interferon were produced to adequately test its abilities as an anti-cancer drug, it was found to be not nearly as effective as had been hoped.

Although genetic engineering would seem to be a marvelous new technique and it surely is that, it also has certain dangers associated with it. One problem is that when the genetic makeup of an organism is altered, it is not possible to predict exactly what the nature of that organism might be. If there is something inherently harmful about the new organism and that organism is released to the environment, the results could be disastrous. This danger is usually dealt with by using, as the host organism, a bacterium which is, somehow deficient and cannot survive outside the laboratory.

Another problem is that a future step in genetic engineering might well involve the ability to alter the genetic makeup of higher organisms, including humans. There are difficult ethical questions involved in how far we should go in changing our own genes, much less those of domestic animals.

Few, perhaps, would argue against the altering of the bone marrow cells of a person with sickle cell anemia to enable him or her to produce normal hemoglobin, a technique by the way, which has not yet been developed. But suppose we were able to genetically slow down, or even halt the aging process, alter fetal cells to produce certain desired characteristics in babies, such as hair color or intelligence, or increase the strength in athletes, or alter our own physiology to enable us to breathe under water, or even clone individuals with certain unique talents. Who should decide what kinds of changes are acceptable and who should be allowed to have their genes or those of their children altered? And what if something goes wrong with the procedure and a defective human is produced? These questions are not easy and the techniques are not without hazard.

Regarding genetic engineering:

(These questions are also given in Exercise 18 in your workbook.)

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E-mail instructor: Sue Eggling

Clackamas Community College 2001, 2003 Clackamas Community College, Hal Bender

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Genetic Engineering - Clackamas Community College

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Genetic Engineering Careers in India : How to become a …

Thursday, August 4th, 2016

Genetic Engineering (GE) is a highly complicated and advanced branch of science which involves a wide range of techniques used in changing the genetic material in the DNA code in a living organism. 'Genetic Engineering' means the deliberate modification of the characters of an organism by the manipulation of its genetic material.Genetic engineering comes under the broad heading of Biotechnology. There is a great scope in this field as the demand for genetic engineers are growing in India as well as abroad.

A cell is the smallest living unit, the basic structural and functional unit of all living matter, whether a plant, an animal, humans or a fungus. While some organisms are single celled, others like plants, animals, humans etc are made up of a lot more cells. For eg humans have approximately 3 million cells. A cell is composed of a 'cell membrane' enclosing the whole cell, many 'organelles' equivalent to the organs in the body and a 'nucleus' which is the command centre of the cell. Inside the nucleus are the chromosomes which is the storage place for all genetic (hereditary) information which determines the nature and characteristics of an organism. This information is written along the thin thread, called DNA, a nucleic acid which constitutes the genes (units of heredity). The DNA governs cell growth and is responsible for the transmission of genetic information from one generation to the next.

Genetic engineering aims to re-arrange the sequence of DNA in gene using artificial methods. The work of a genetic engineer involves extracting the DNA out of one organism, changing it using chemicals or radiation and subsequently putting it back into the same or a different organism. For eg: genes and segments of DNA from one species is taken and put into another species. They also study how traits and characteristics are transmitted through the generations, and how genetic disorders are caused. Their research involves researching the causes and discovering potential cures if any.

Genetic engineering have specialisations related to plants, animals and human beings. Genetic engineering in plants and animals may be to improve certain natural characteristics of value, to increase resistance to disease or damage and to develop new characteristics etc. It is used to change the colour, size, texture etc of plants otherwise known as GM (Genetically Modified) foods.GE in humans can be to correct severe hereditary defects by introducing normal genes into cells in place of missing or defective ones.

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Genetic engineering – Friends of the Earth

Thursday, August 4th, 2016

We have a right to food that is good for our bodies and our environment. Numerous studies show that genetically engineered foods can pose serious risks to both. Yet the U.S. Department of Agriculture keeps approving genetically engineered crops that benefit a few biotech corporations. At the same time, the Food and Drug Administration is considering approving the first-ever genetically engineered animal for human consumption, a genetically engineered salmon created by AquaBounty Technologies that supposedly grows twice as fast as its natural counterpart.

Friends of the Earth is working to keep this "frankenfish" and other genetically engineered foods off of grocery store shelves, and to ensure that all genetically engineered foods are labeled so that consumers can choose whether to feed these risky products to their families.

Research shows that genetically engineered fish pose numerous risks to wild fish populations. Of particular concern is the survival of natural Atlantic salmon, which is already listed as endangered. Research published by the Canadian government has found that genetically engineered salmon, if released into the wild, could lead to a collapse of wild populations. Genetically engineered salmon may be able to mate with wild populations, weakening their gene pool, and could even out-compete wild salmon for food, leading to ecosystem-wide impacts.

Human health is threatened too. The approval of the frankenfish would likely lead to the use of even more antibiotics in aquaculture, increasing the risks of drug-resistant bacteria and viruses. Farmed salmon are given more antibiotics than any other livestock by weight, and the companys data shows the frankenfish may require even more antibiotics, as the engineered fish could be more susceptible to disease.

Despite concerns raised by scientists, the FDA has not yet conducted a thorough, independent analysis of the dangers frankenfish pose to people or the environment.

We are pushing the FDA to take a rigorous look at the risks, partnering with members of Congress on laws to prevent the spread of genetically engineered foods and mandate labels and mobilizing the public to take action to protect our health, biodiversity and our right to choose healthy food. Check out our issue brief on the risks posed by genetically engineered fish to learn more.

Genetic engineering is moving beyond our food and agricultural systems. Friends of the Earth is also working to prevent the release of genetically engineered mosquitoes and other insects in the U.S. until proper laws have been written and risk assessments conducted to ensure these genetically engineered bugs don't harm humans or our ecosystems. Check out our issue brief on genetically engineered mosquitoes to learn more.

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Genetic engineering – Simple English Wikipedia, the free …

Thursday, August 4th, 2016

Genetic engineering (GE), also called genetic modification, is a branch of applied biology. It is the changing of an organism's genome using biotechnology. These methods are recent discoveries. The techniques are advanced, and full details are not given here.

This is an overview of what can be done:

An organism that is altered by genetic engineering is a genetically modified organism (GMO). The first GMOs were bacteria in 1973;[2] GM mice were made in 1974. Insulin-producing bacteria were commercialized in 1982. Genetically modified food has been sold since 1994, including crops.

Genetic engineering techniques have been used in research, agriculture, industrial biotechnology, and medicine. Enzymes used in laundry detergent, and medicines such as insulin and human growth hormone are now manufactured in GM cells. GM animals such as mice or zebrafish are being used for research purposes.

Critics have objected to use of genetic engineering on several grounds, including ethical concerns, ecological concerns. Economic concerns are raised by the fact GM techniques and GM organisms are subject to intellectual property law. Ecological concerns are more subtle. There is a risk that some genetically modified (GM) organisms may be better adapted to some niche in nature, and will take away some the habitat of the regular species.

The ability to construct long base pair chains cheaply and accurately on a large scale allows researchers to do experiments on genomes that do not exist in nature. The field of 'synthetic genomics' is beginning to enter a productive stage.

The J. Craig Venter Institute has built a quasi-synthetic Mycoplasma genitalium yeast genome. They recombined 25 overlapping fragments in a single step. "The use of yeast recombination greatly simplifies the assembly of large DNA molecules from both synthetic and natural fragments".[3] Other companies, such as Synthetic Genomics, have already been formed to take advantage of the many commercial uses of custom designed genomes.

The team of about 20 researchers is led by Nobel laureate Hamilton Smith, DNA researcher Craig Venter and microbiologist Clyde A. Hutchison III. They plan to create Mycoplasma laboratorium a partially synthetic species of bacterium derived from the genome of Mycoplasma genitalium.

Geneticists have made the first synthetic chromosome for yeast.

As a eukaryote, yeast has cells with a nucleus. Often classified as a fungus, yeast is related to plants and animals and shares 2,000 genes with ourselves.

The creation of the first of yeast's 16 chromosomes has been hailed as "a massive deal" in the emerging science of synthetic biology.[4]

GMOs also are involved in controversies over GM food, as to whether food produced from GM crops is safe, whether it should be labeled, and whether GM crops are needed to address the world's food needs. These controversies have led to litigation, international trade disputes, and protests, and to restrictive regulation of commercial products in most countries.

We can now produce and use GM and GE seeds. Some large countries like India and China have already decided that GM farming is what they need to feed their populations. Other countries are still debating the issue.[5] This debate involves scientists, farmers, politicians, companies and UN agencies. Even those involved in the production of GM seedlings are not in total agreement.[5]

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Genetic engineering – Memory Alpha – Wikia

Thursday, August 4th, 2016

A portrait of Khan Noonien Singh, a man who was a product of genetic engineering

Genetic engineering, or genetic manipulation was a process in which the DNA of an organism was selectively altered through artificial means. Genetic engineering was often used to produce "custom" organisms, such as for agricultural or medical purposes, as well as to produce biogenic weapons. The most common application of genetic engineering on intelligent beings in the Federation was corrective DNA resequencing for genetic disorders. A far more dubious application of genetic engineering was the genetic enhancement of individuals to produce improved senses, strength, intelligence, etc.

During Earth's 20th century, efforts to produce "superhumans" resulted in the Eugenics Wars. Genetically engineered individuals such as Khan Noonien Singh attempted to seize power. (TOS: "Space Seed")

This would lead to the banning of genetic engineering on Earth by the mid-22nd century, even research which could be used to cure critical illnesses. This ban was implemented because of the general fear of creating more tyrants such as Khan. It was also felt that parents would feel compelled to have their children genetically engineered, especially if "enhanced" individuals were allowed to compete in normal society.

Some, including geneticist Arik Soong, argued that it was simply convenient for humanity to denounce the attempts at genetic "improvement" of humanity, that it was inherently evil because of the Eugenics Wars. He argued that the source of the problem, in fact, wasn't the technology, but humanity's own inability to use it wisely. Imprisoned for, among other crimes, stealing the embryos of a number of Augment children, Soong wrote long treatises on the subject of genetic augmentations and improvements. His works were routinely taken and placed into storage (although his jailers often told him that his work was vaporized). Captain Jonathan Archer expressed his hope to Soong that research into genetic engineering that could cure life-threatening diseases would someday be resumed. (ENT: "Borderland", "The Augments")

Others, however, chose to establish isolated colonies, as became the case with the Genome colony on Moab IV, which was established in 2168. It became a notable and successful example of Human genetic engineering in which every individual was genetically tailored from birth to perform a specific role in society. However, after a five-day visit by the USS Enterprise-D when the ship came to the colony in an effort to save it from an approaching neutron star which, eventually, the craft was able to effectively redirect twenty-three colonists left the colony aboard the craft, possibly causing significant damage to the structure of their society. The reason for the societal split was that those who left the colony had realized their organized, pre-planned world had certain limitations, lacking opportunities to grow that were offered by the Enterprise. (TNG: "The Masterpiece Society")

By the 24th century, the United Federation of Planets allowed limited use of genetic engineering to correct existing genetically related medical conditions. Persons known to be genetically enhanced, however, were not allowed to serve in Starfleet, and were especially banned from practicing medicine. (TNG: "Genesis", DS9: "Doctor Bashir, I Presume")

Nevertheless, some parents attempted to secretly have their children genetically modified. (DS9: "Doctor Bashir, I Presume") Unfortunately, most of these operations were performed by unqualified physicians, resulting in severe psychological problems in the children due to their enhancements being only partially successful, such as a patient's senses being enhanced while their ability to process the resulting data remained at a Human norm. (DS9: "Statistical Probabilities")

In some cases, genetic engineering can be permitted to be performed in utero when dealing with a developing fetus to correct any potential genetic defects that could handicap the child as they grew up. Chakotay's family history included a defective gene that made those who possessed it prone to hallucinations, the gene afflicting his grandfather in Chakotay's youth, although the gene was suppressed in Chakotay himself. (VOY: "The Fight") In 2377, The Doctor performed prenatal genetic modification on Miral Paris to correct a spinal deviation, a congenital defect that tends to run in Klingon families; Miral's mother had undergone surgery to correct the defect in herself at a young age. (VOY: "Lineage")

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Genetic Engineering – Genetic Diseases

Thursday, August 4th, 2016

Although not completely related to genetic disorders, genetic engineering has its applications in genetic diseases area. In the world around us today, thanks to the progress of science and technology, man has to a large extent taken the responsibility of shaping as well as the mutating the natural world around us in a way that can prove to be more profitable to all of us. Genetic Engineering is, in, such a scenario, a tool that is gradually coming in more and more focus as a means of shaping the world to map to our needs and requirements.

Where can we see genetic engineering around us today?

While going out for grocery shopping, we often come across fruits, vegetables, as well as cereals, all of which have been genetically engineered or modified to mutate their nature structure in order to make them more hygienic, more palatable as well as more nutritious. In some cases, the use of genetic engineering is also conducted to remove the harmful ingredients of a substance in order to make it more accessible for people who have certain maladies. An example of this could be genetically engineered potatoes in which the sugar content has been removed to allow them to be consumed by diabetics.

However, the use of genetic engineering can have certain pitfalls and negative aspects as well, which has led to a huge debate world wide amongst scientists and technologists.

What is genetic engineering?

The DNA can be said to be the main point of origin of the living body which is in actuality a sort of blue print which allows the shaping and growth of every aspect of a living organism. Through the process of genetic engineering, the DNA of the living body is transformed and mutated by scientists, who can, through this process engineer the growth as well as the different qualities and characteristics which make up the living being.

How is genetic engineering different from the process of traditional breeding?

The science of genetic engineering has often been compared to other and older versions of the process such as traditional breeding of cells. However, the most important difference between the two processes of genetic engineering as well as the traditional breeding process is the fact that in the case of the process of traditional breeding, the mutation of the genes of the living organism is carried out as an external process.

However, in the case of the more recent processes of genetic engineering, the cells of the living organisms are mutated, modified, created or destroyed while they are within the organism itself. These processes are in turn dependent on the twin processes of molecular cloning as well as transformation, through which the qualities of the genes of the organism are transformed to add or destroy the natural characteristics of the organism.

Can genetic engineering be used in the cases of human beings?

Though the field of the studies associated with human genetic engineering is an extremely vibrant one and studies are still on to discover more facets to it, the field today has shown immense potential in displaying an ability to cure several diseases which are associated with or formed due to an abnormality or deficiency in the structure of the human genes.

Genetic engineering can be seen to have the potential to cure several diseases and also act as a medium in order to change an individuals appearance, voice, intelligence, behavior as well as his or her characteristics.

How is genetic engineering carried out in the case of human beings?

The science of human genetic engineering works by using various scientific processes to modify or transform the genotype of the individual by selecting and opting for a specific phenotype of the human being in the case of infants as well as new born babies. On the other hand, in the cases of matured adults, the science aims to change the natural phenotype of the individual with a phenotype that has been customized.

Advantages of using genetic engineering

Though there are several debates which are raging all around the world both for and against the science of human genetic engineering, the advantages of using human genetic engineering in the process of curing several presently incurable diseases which stem from the human genetic structure cannot be ruled out. If used properly, the science of human genetic engineering can help in curing diseases such as:

Besides this, the science can also be used to ensure that all babies are born healthy as any form of genetic disorder observed in the fetus can be cured before the baby is born.

Disadvantages of using genetic engineering

There are also several disadvantages which are associated with the science of genetic engineering. Notable among this is the fact that while using this, man will again be a product of mechanics and science. Out individuality will be lost. Besides this, the process can be quite expensive and many third world countries may not be bale to use this even for treating critically ill patients.

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Genetic Engineering - Genetic Diseases

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History of genetic engineering – Wikipedia, the free …

Thursday, August 4th, 2016

Genetic modification caused by human activity has been occurring since around 12,000 BC, when humans first began to domesticate organisms. Genetic engineering as the direct transfer of DNA from one organism to another was first accomplished by Herbert Boyer and Stanley Cohen in 1973. The first genetically modified animal was a mouse created in 1973 by Rudolf Jaenisch. In 1983 an antibiotic resistant gene was inserted into tobacco, leading to the first genetically engineered plant. Advances followed that allowed scientists to manipulate and add genes to a variety of different organism and induce a range of different effects.

In 1976 the technology was commercialised, with the advent of genetically modified bacteria that produced somatostatin, followed by insulin in 1978. Plants were first commercialised with virus resistant tobacco released in China in 1992. The first genetically modified food was the Flavr Savr tomato marketed in 1994. By 2010, 29 countries had planted commercialized biotech crops. In 2000 a paper published in Science introduced golden rice, the first food developed with increased nutrient value.

Genetic engineering is the direct manipulation of an organism's genome using certain biotechnology techniques that have only existed since the 1970s.[2] Human directed genetic manipulation was occurring much earlier, beginning with the domestication of plants and animals through artificial selection. The dog is believed to be the first animal domesticated, possibly arising from a common ancestor of the grey wolf,[1] with archeologically evidence dating to about 12,000 BC.[3] Other carnivores domesticated in prehistoric times include the cat, which cohabited with human 9 500 years ago.[4] Archeologically evidence suggests sheep, cattle, pigs and goats were domesticated between 9 000 BC and 8 000 BC in the Fertile Crescent.[5]

The first evidence of plant domestication comes from emmer and einkorn wheat found in pre-Pottery Neolithic A villages in Southwest Asia dated about 10,500 to 10,100 BC. The Fertile Crescent of Western Asia, Egypt, and India were sites of the earliest planned sowing and harvesting of plants that had previously been gathered in the wild. Independent development of agriculture occurred in northern and southern China, Africa's Sahel, New Guinea and several regions of the Americas.[7] The eight Neolithic founder crops (emmer wheat, einkorn wheat, barley, peas, lentils, bitter vetch, chick peas and flax) had all appeared by about 7000 BC.[8]Horticulture first appears in the Levant during the Chalcolithic period about 6 800 to 6,300 BC. Due to the soft tissues, archeological evidence for early vegetables is scarce. The earliest vegetable remains have been found in Egyptian caves that date back to the 2nd millennium BC.

Selective breeding of domesticated plants was once the main way early farmers shaped organisms to suit their needs. Charles Darwin described three types of selection: methodical selection, wherein humans deliberately select for particular characteristics; unconscious selection, wherein a characteristic is selected simply because it is desirable; and natural selection, wherein a trait that helps an organism survive better is passed on.[11]:25 Early breeding relied on unconscious and natural selection. The introduction of methodical selection is unknown.[11]:25 Common characteristics that were bred into domesticated plants include grains that did not shatter to allow easier harvesting, uniform ripening, shorter lifespans that translate to faster growing, loss of toxic compounds, and productivity.[11]:2730 Some plants, like the Banana, were able to be propagated by vegetative cloning. Offspring often did not contain seeds, and therefore sterile. However, these offspring were usually juicier and larger. Propagation through cloning allows these mutant varieties to be cultivated despite their lack of seeds.[11]:31

Hybridization was another way that rapid changes in plant's makeup were introduced. It often increased vigor in plants, and combined desirable traits together. Hybridization most likely first occurred when humans first grew similar, yet slightly different plants in close proximity.[11]:32Triticum aestivum, wheat used in baking bread, is an allopolyploid. Its creation is the result of two separate hybridization events.[12]

X-rays were first used to deliberately mutate plants in 1927. Between 1927 and 2007, more than 2,540 genetically mutated plant varieties had been produced using x-rays.[13]

Various genetic discoveries have been essential in the development of genetic engineering. Genetic inheritance was first discovered by Gregor Mendel in 1865 following experiments crossing peas. Although largely ignored for 34 years he provided the first evidence of hereditary segregation and independent assortment.[14] In 1889 Hugo de Vries came up with the name "(pan)gene" after postulating that particles are responsible for inheritance of characteristics[15] and the term "genetics" was coined by William Bateson in 1905.[16] In 1928 Frederick Griffith proved the existence of a "transforming principle" involved in inheritance, which Avery, MacLeod and McCarty later (1944) identified as DNA. Edward Lawrie Tatum and George Wells Beadle developed the central dogma that genes code for proteins in 1941. The double helix structure of DNA was identified by James Watson and Francis Crick in 1953.

As well as discovering how DNA works, tools had to be developed that allowed it to be manipulated. In 1970 Hamilton Smiths lab discovered restriction enzymes that allowed DNA to be cut at specific places and separated out on an electrophoresis gel. This enabled scientists to isolate genes from an organism's genome.[17]DNA ligases, that join broken DNA together, had been discovered earlier in 1967[18] and by combining the two enzymes it was possible to "cut and paste" DNA sequences to create recombinant DNA. Plasmids, discovered in 1952,[19] became important tools for transferring information between cells and replicating DNA sequences. Frederick Sanger developed a method for sequencing DNA in 1977, greatly increasing the genetic information available to researchers. Polymerase chain reaction (PCR), developed by Kary Mullis in 1983, allowed small sections of DNA to be amplified and aided identification and isolation of genetic material.

As well as manipulating the DNA, techniques had to be developed for its insertion (known as transformation) into an organism's genome. Griffiths experiment had already shown that some bacteria had the ability to naturally uptake and express foreign DNA. Artificial competence was induced in Escherichia coli in 1970 when Morton Mandel and Akiko Higa showed that it could take up bacteriophage after treatment with calcium chloride solution (CaCl2).[20] Two years later, Stanley Cohen showed that CaCl2 treatment was also effective for uptake of plasmid DNA.[21] Transformation using electroporation was developed in the late 1980s, increasing the efficiency and bacterial range.[22] In 1907 a bacterium that caused plant tumors, Agrobacterium tumefaciens, was discovered and in the early 1970s the tumor inducing agent was found to be a DNA plasmid called the Ti plasmid.[23] By removing the genes in the plasmid that caused the tumor and adding in novel genes researchers were able to infect plants with A. tumefaciens and let the bacteria insert their chosen DNA into the genomes of the plants.[24]

In 1972 Paul Berg utilised restriction enzymes and DNA ligases to create the first recombinant DNA molecules. He combined DNA from the monkey virus SV40 with that of the lambda virus.[25]Herbert Boyer and Stanley N. Cohen took Berg's work a step further and introduced recombinant DNA into a bacterial cell. Cohen was researching plasmids, while Boyers work involved restriction enzymes. They recognised the complementary nature of their work and teamed up in 1972. Together they found a restriction enzyme that cut the pSC101 plasmid at a single point and were able to insert and ligate a gene that conferred resistance to the kanamycin antibiotic into the gap. Cohen had previously devised a method where bacteria could be induced to take up a plasmid and using this they were able to create a bacteria that survived in the presence of the kanamycin. This represented the first genetically modified organism. They repeated experiments showing that other genes could be expressed in bacteria, including one from the toad Xenopus laevis, the first cross kingdom transformation.[26][27][28]

In 1973 Rudolf Jaenisch created a transgenic mouse by introducing foreign DNA into its embryo, making it the worlds first transgenic animal.[29] Jaenisch was studying mammalian cells infected with simian virus 40 (SV40) when he happened to read a paper from Beatrice Mintz describing the generation of chimera mice. He took his SV40 samples to Mintz's lab and injected them into early mouse embryos expecting tumours to develop. The mice appeared normal, but after using radioactive probes he discovered that the virus had integrated itself into the mice genome.[30] However the mice did not pass the transgene to their offspring. In 1981 the laboratories of Frank Ruddle, Frank Constantini and Elizabeth Lacy injected purified DNA into a single-cell mouse embryo and showed transmission of the genetic material to subsequent generations.[31][32]

The first genetically engineered plant was tobacco, reported in 1983.[33] It was developed by Michael W. Bevan, Richard B. Flavell and Mary-Dell Chilton by creating a chimeric gene that joined an antibiotic resistant gene to the T1 plasmid from Agrobacterium. The tobacco was infected with Agrobacterium transformed with this plasmid resulting in the chimeric gene being inserted into the plant. Through tissue culture techniques a single tobacco cell was selected that contained the gene and a new plant grown from it.[34]

The development of genetic engineering technology led to concerns in the scientific community about potential risks. The development of a regulatory framework concerning genetic engineering began in 1975, at Asilomar, California. The Asilomar meeting recommended a set of guidelines regarding the cautious use of recombinant technology and any products resulting from that technology.[35] The Asilomar recommendations were voluntary, but in 1976 the US National Institute of Health (NIH) formed a recombinant DNA advisory committee.[36] This was followed by other regulatory offices (the United States Department of Agriculture (USDA), Environmental Protection Agency (EPA) and Food and Drug Administration (FDA)), effectively making all recombinant DNA research tightly regulated in the USA.[37]

In 1982 the Organization for Economic Co-operation and Development (OECD) released a report into the potential hazards of releasing genetically modified organisms into the environment as the first transgenic plants were being developed.[38] As the technology improved and genetically organisms moved from model organisms to potential commercial products the USA established a committee at the Office of Science and Technology (OSTP) to develop mechanisms to regulate the developing technology.[37] In 1986 the OSTP assigned regulatory approval of genetically modified plants in the US to the USDA, FDA and EPA.[39] In the late 1980s and early 1990s, guidance on assessing the safety of genetically engineered plants and food emerged from organizations including the FAO and WHO.[40][41][42][43]

The European Union first introduced laws requiring GMO's to be labelled in 1997.[44] In 2013 Connecticut became the first state to enacted a labeling law in the USA, although it would not take effect until other states followed suit.[45]

The ability to insert, alter or remove genes in model organisms allowed scientists to study the genetic elements of human diseases.[46]Genetically modified mice were created in 1984 that carried cloned oncogenes that predisposed them to developing cancer.[47] The technology has also been used to generate mice with genes knocked out. The first recorded knockout mouse was created by Mario R. Capecchi, Martin Evans and Oliver Smithies in 1989. In 1992 oncomice with tumor suppressor genes knocked out were generated.[47] Creating Knockout rats is much harder and only became possible in 2003.[48][49]

After the discovery of microRNA in 1993,[50]RNA interference (RNAi) has been used to silence an organism's genes.[51] By modifying an organism to express mircoRNA targeted to its endogenous genes, researchers have been able to knockout or partially reduce gene function in a range of species. The ability to partially reduce gene function has allowed the study of genes that are lethal when completely knocked out. Other advantages of using RNAi include the availability of inducible and tissue specific knockout.[52] In 2007 microRNA targeted to insect and nematode genes was expressed in plants, leading to suppression when they fed on the transgenic plant, potentially creating a new way to control pests.[53] Targeting endogenous microRNA expression has allowed further fine tuning of gene expression, supplementing the more traditional gene knock out approach.[54]

Genetic engineering has been used to produce proteins derived from humans and other sources in organisms that normally cannot synthesize these proteins. Human insulin-synthesising bacteria were developed in 1979 and were first used as a treatment in 1982.[55] In 1988 the first human antibodies were produced in plants.[56] In 2000 Vitamin A-enriched golden rice, was the first food with increased nutrient value.[57]

As not all plant cells were susceptible to infection by A. tumefaciens other methods were developed, including electroporation, micro-injection[58] and particle bombardment with a gene gun (invented in 1987).[59][60] In the 1980s techniques were developed to introduce isolated chloroplasts back into a plant cell that had its cell wall removed. With the introduction of the gene gun in 1987 it became possible to integrate foreign genes into a chloroplast.[61]

Genetic transformation has become very efficient in some model organism. In 2008 genetically modified seeds were produced in Arabidopsis thaliana by simply dipping the flowers in an Agrobacterium solution.[62] The range of plants that can be transformed has increased as tissue culture techniques have been developed for different species.

The first transgenic livestock were produced in 1985,[63] by micro-injecting foreign DNA into rabbit, sheep and pig eggs.[64] The first animal to synthesise transgenic proteins in their milk were mice,[65] engineered to produce human tissue plasminogen activator.[66] This technology was applied to sheep, pigs, cows and other livestock.[65]

In 2010 scientists at the J. Craig Venter Institute announced that they had created the first synthetic bacterial genome. The researchers added the new genome to bacterial cells and selected for cells that contained the new genome. To do this the cells undergoes a process called resolution, where during bacterial cell division one new cell receives the original DNA genome of the bacteria, whilst the other receives the new synthetic genome. When this cell replicates it uses the synthetic genome as its template. The resulting bacterium the researchers developed, named Synthia, was the world's first synthetic life form.[67][68]

In 2014 a bacteria was developed that replicated a plasmid containing an unnatural base pair. This required altering the bacterium so it could import the unnatural nucleotides and then efficiently replicate them. The plasmid retained the unnatural base pairs when it doubled an estimated 99.4% of the time.[69] This is the first organism engineered to use an expanded genetic alphabet.[70]

In 2015 CRISPR and TALENs was used to modify plant genomes. Chinese labs used it to create a fungus-resistant wheat and boost rice yields, while a U.K. group used it to tweak a barley gene that could help produce drought-resistant varieties. When used to precisely remove material from DNA without adding genes from other species, the result is not subject the lengthy and expensive regulatory process associated with GMOs. While CRISPR may use foreign DNA to aid the editing process, the second generation of edited plants contain none of that DNA. Researchers celebrated the acceleration because it may allow them to "keep up" with rapidly evolving pathogens. The U.S. Department of Agriculture stated that some examples of gene-edited corn, potatoes and soybeans are not subject to existing regulations. As of 2016 other review bodies had yet to make statements.[71]

In 1976 Genentech, the first genetic engineering company was founded by Herbert Boyer and Robert Swanson and a year later and the company produced a human protein (somatostatin) in E.coli. Genentech announced the production of genetically engineered human insulin in 1978.[72] In 1980 the U.S. Supreme Court in the Diamond v. Chakrabarty case ruled that genetically altered life could be patented.[73] The insulin produced by bacteria, branded humulin, was approved for release by the Food and Drug Administration in 1982.[74]

In 1983 a biotech company, Advanced Genetic Sciences (AGS) applied for U.S. government authorization to perform field tests with the ice-minus strain of P. syringae to protect crops from frost, but environmental groups and protestors delayed the field tests for four years with legal challenges.[75] In 1987 the ice-minus strain of P. syringae became the first genetically modified organism (GMO) to be released into the environment[76] when a strawberry field and a potato field in California were sprayed with it.[77] Both test fields were attacked by activist groups the night before the tests occurred: "The world's first trial site attracted the world's first field trasher".[76]

The first genetically modified crop plant was produced in 1982, an antibiotic-resistant tobacco plant.[78] The first field trials of genetically engineered plants occurred in France and the USA in 1986, tobacco plants were engineered to be resistant to herbicides.[79] In 1987 Plant Genetic Systems, founded by Marc Van Montagu and Jeff Schell, was the first company to genetically engineer insect-resistant plants by incorporating genes that produced insecticidal proteins from Bacillus thuringiensis (Bt) into tobacco.[80]

Genetically modified microbial enzymes were the first application of genetically modified organisms in food production and were approved in 1988 by the US Food and Drug Administration.[81] In the early 1990s, recombinant chymosin was approved for use in several countries.[81][82] Cheese had typically been made using the enzyme complex rennet that had been extracted from cows' stomach lining. Scientists modified bacteria to produce chymosin, which was also able to clot milk, resulting in cheese curds.[83] The Peoples Republic of China was the first country to commercialize transgenic plants, introducing a virus-resistant tobacco in 1992.[84] In 1994 Calgene attained approval to commercially release the Flavr Savr tomato, a tomato engineered to have a longer shelf life.[85] Also in 1994, the European Union approved tobacco engineered to be resistant to the herbicide bromoxynil, making it the first genetically engineered crop commercialized in Europe.[86] In 1995 Bt Potato was approved safe by the Environmental Protection Agency, after having been approved by the FDA, making it the first pesticide producing crop to be approved in the USA.[87] In 1996 a total of 35 approvals had been granted to commercially grow 8 transgenic crops and one flower crop (carnation), with 8 different traits in 6 countries plus the EU.[79]

By 2010, 29 countries had planted commercialized biotech crops and a further 31 countries had granted regulatory approval for transgenic crops to be imported.[88] In 2013 Robert Fraley (Monsantos executive vice president and chief technology officer), Marc Van Montagu and Mary-Dell Chilton were awarded the World Food Prize for improving the "quality, quantity or availability" of food in the world.[89]

The first genetically modified animal to be commercialised was the GloFish, a Zebra fish with a fluorescent gene added that allows it to glow in the dark under ultraviolet light.[90] The first genetically modified animal to be approved for food use was AquAdvantage salmon in 2015.[91] The salmon were transformed with a growth hormone-regulating gene from a Pacific Chinook salmon and a promoter from an ocean pout enabling it to grow year-round instead of only during spring and summer.[92]

Opposition and support for the use of genetic engineering has existed since the technology was developed.[76] After Arpad Pusztai went public with research he was conducting in 1998 the public opposition to genetically modified food increased.[93] Opposition continued following controversial and publicly debated papers published in 1999 and 2013 that claimed negative environmental and health impacts from genetically modified crops.[94][95]

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Genetic Engineering – The New York Times

Thursday, August 4th, 2016

Latest Articles

A Senate bill that would prevent states from requiring food labels to note the presence of genetically modified ingredients failed on Wednesday.

By STEPHANIE STROM

The senators will consider whether the government should require labeling on foods containing genetically engineered ingredients, an issue that has split the food industry.

By JENNIFER STEINHAUER and STEPHANIE STROM

A trial in the Florida Keys has been tentatively approved, but public comment must be assessed first by the agency.

By ANDREW POLLACK

A diverse biotechnology company hopes its genetically engineered mosquitoes can help stop the spread of a devastating virus. But thats just a start.

By ANDREW POLLACK

An official of a dairy association says G.M.O. products are safe and that any labeling rules should be national, not state by state.

States should be free to require the labeling of genetically modified food if they want to.

By THE EDITORIAL BOARD

.

By PAM BELLUCK

Researchers worldwide have been observing a voluntary moratorium on changes to DNA that could be passed down to subsequent generations.

By NICHOLAS WADE

Genetically engineered mosquitoes are among the cutting-edge weapons being tested against diseases, even as some experts say old-fashioned tools like DDT may be worth discussing.

By ANDREW POLLACK

A reader has ethical concerns about research that consigns deeply social animals to a lifetime of severe anxiety and isolation.

Scientists in Shanghai are trying to locate the deficiency in the brain circuits responsible for autism-like behavior found in genetically engineered monkeys.

By PAM BELLUCK

A potato genetically engineered to resist the pathogen that caused the Irish potato famine is as safe as any other potato on the market, the Food and Drug Administration says.

Campbell Soup breaks from its rival food companies to disclose the presence of genetically engineered ingredients in its products.

By STEPHANIE STROM

Three research groups, working independently of one another, reported in the journal Science on Thursday that a powerful new gene-editing technique could treat Duchenne muscular dystrophy in mice.

By NICHOLAS WADE

The technique involves propelling a gene of choice throughout a population. It hasnt been tested in the wild yet, but has worked in the laboratory.

By NICHOLAS WADE

An international panel was right to call for a moratorium on a new technique that alters genes in ways that can be inherited.

By THE EDITORIAL BOARD

Congress should stop a backdoor effort to insert language in the omnibus spending bill that would bar states from passing G.M.O. labeling laws.

By TOM COLICCHIO

Readers discuss an editorial endorsing such labeling.

The call for a moratorium by China, Britain and the United States comes after the invention of a new technique that eases editing of the human genome.

By NICHOLAS WADE

Congress should overturn the Food and Drug Administrations decision not to require labeling of genetically engineered salmon.

By THE EDITORIAL BOARD

A Senate bill that would prevent states from requiring food labels to note the presence of genetically modified ingredients failed on Wednesday.

By STEPHANIE STROM

The senators will consider whether the government should require labeling on foods containing genetically engineered ingredients, an issue that has split the food industry.

By JENNIFER STEINHAUER and STEPHANIE STROM

A trial in the Florida Keys has been tentatively approved, but public comment must be assessed first by the agency.

By ANDREW POLLACK

A diverse biotechnology company hopes its genetically engineered mosquitoes can help stop the spread of a devastating virus. But thats just a start.

By ANDREW POLLACK

An official of a dairy association says G.M.O. products are safe and that any labeling rules should be national, not state by state.

States should be free to require the labeling of genetically modified food if they want to.

By THE EDITORIAL BOARD

.

By PAM BELLUCK

Researchers worldwide have been observing a voluntary moratorium on changes to DNA that could be passed down to subsequent generations.

By NICHOLAS WADE

Genetically engineered mosquitoes are among the cutting-edge weapons being tested against diseases, even as some experts say old-fashioned tools like DDT may be worth discussing.

By ANDREW POLLACK

A reader has ethical concerns about research that consigns deeply social animals to a lifetime of severe anxiety and isolation.

Scientists in Shanghai are trying to locate the deficiency in the brain circuits responsible for autism-like behavior found in genetically engineered monkeys.

By PAM BELLUCK

A potato genetically engineered to resist the pathogen that caused the Irish potato famine is as safe as any other potato on the market, the Food and Drug Administration says.

Campbell Soup breaks from its rival food companies to disclose the presence of genetically engineered ingredients in its products.

By STEPHANIE STROM

Three research groups, working independently of one another, reported in the journal Science on Thursday that a powerful new gene-editing technique could treat Duchenne muscular dystrophy in mice.

By NICHOLAS WADE

The technique involves propelling a gene of choice throughout a population. It hasnt been tested in the wild yet, but has worked in the laboratory.

By NICHOLAS WADE

An international panel was right to call for a moratorium on a new technique that alters genes in ways that can be inherited.

By THE EDITORIAL BOARD

Congress should stop a backdoor effort to insert language in the omnibus spending bill that would bar states from passing G.M.O. labeling laws.

By TOM COLICCHIO

Readers discuss an editorial endorsing such labeling.

The call for a moratorium by China, Britain and the United States comes after the invention of a new technique that eases editing of the human genome.

By NICHOLAS WADE

Congress should overturn the Food and Drug Administrations decision not to require labeling of genetically engineered salmon.

By THE EDITORIAL BOARD

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Genetic Engineering - The New York Times

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Redesigning the World: Ethical Questions About Genetic …

Thursday, August 4th, 2016

Redesigning the World Ethical Questions about Genetic Engineering

Ron Epstein 1

INTRODUCTION

Until the demise of the Soviet Union, we lived under the daily threat of nuclear holocaust extinguishing human life and the entire biosphere. Now it looks more likely that total destruction will be averted, and that widespread, but not universally fatal, damage will continue to occur from radiation accidents from power plants, aging nuclear submarines, and perhaps the limited use of tactical nuclear weapons by governments or terrorists.

What has gone largely unnoticed is the unprecedented lethal threat of genetic engineering to life on the planet. It now seems likely, unless a major shift in international policy occurs quickly, that the major ecosystems that support the biosphere are going to be irreversibly disrupted, and that genetically engineered viruses may very well lead to the eventual demise of almost all human life. In the course of the major transformations that are on the way, human beings will be transformed, both intentionally and unintentionally, in ways that will make us something different than what we now consider human.

Heedless of the dangers, we are rushing full speed ahead on almost all fronts. Some of the most powerful multinational chemical, pharmaceutical and agricultural corporations have staked their financial futures on genetic engineering. Enormous amounts of money are already involved, and the United States government is currently bullying the rest of the world into rapid acceptance of corporate demands concerning genetic engineering research and marketing.

WHAT IS GENETIC ENGINEERING

What are genes?

Genes are often described as 'blueprints' or 'computer programs' for our bodies and all living organisms. Although it is true that genes are specific sequences of DNA (deoxyribonucleic acid) that are central to the production of proteins, contrary to popular belief and the now outmoded standard genetic model, genes do not directly determine the 'traits' of an organism.1a They are a single factor among many. They provide the 'list of ingredients' which is then organized by the 'dynamical system' of the organism. That 'dynamical system' determines how the organism is going to develop. In other words, a single gene does not, in most cases, exclusively determine either a single feature of our bodies or a single aspect of our behavior. A recipe of ingredients alone does not create a dish of food. A chef must take those ingredients and subject them to complex processes which will determine whether the outcome is mediocre or of gourmet quality. So too the genes are processed through the self-organizing ('dynamical') system of the organism, so that the combination of a complex combination of genes is subjected to a variety of environmental factors which lead to the final results, whether somatic or behavioral.2

a gene is not an easily identifiable and tangible object. It is not only the DNA sequence which determines its functions in the organisms, but also its location in a specific chromosomal, cellular, physiological and evolutionary context. It is therefore difficult to predict the impact of genetic material transfer on the functioning of the extremely tightly controlled, integrated and balanced functioning of all the tens of thousands of structures and processes that make up the body of any complex organism.3

Genetic engineering refers to the artificial modification of the genetic code of a living organism. Genetic engineering changes the fundamental physical nature of the organism, sometimes in ways that would never occur in nature. Genes from one organism are inserted in another organism, most often across natural species boundaries. Some of the effects become known, but most do not. The effects of genetic engineering which we know are ususally short-term, specific and physical. The effects we do not know are often long-term, general, and also mental. Long-term effects may be either specific4 or general.

Differences between Bioengineering and Breeding

The breeding of animals and plants speeds up the natural processes of gene selection and mutation that occur in nature to select new species that have specific use to humans. Although the selecting of those species interferes with the natural selection process that would otherwise occur, the processes utilized are found in nature. For example, horses are bred to run fast without regard for how those thoroughbreds would be able to survive in the wild. There are problems with stocking streams with farmed fish because they tend to crowd out natural species, be less resistant to disease, and spread disease to wild fish.5

The breeding work of people like Luther Burbank led to the introduction of a whole range of tasty new fruits. At the University of California at Davis square tomatoes with tough skins were developed for better packing and shipping. Sometimes breeding goes awry. Killer bees are an example. Another example is the 1973 corn blight that killed a third of the crop that year. It was caused by a newly bred corn cultivar that was highly susceptible to a rare variant of a common leaf fungus.6

Bioengineers often claim that they are just speeding up the processes of natural selection and making the age-old practices of breeding more efficient. In some cases that may be true, but in most instances the gene changes that are engineered would never occur in nature, because they cross natural species barriers.

HOW GENETIC ENGINEERING IS CURRENTLY USED

Here is a brief summary of some of the more important, recent developments in genetic engineering.7

1) Most of the genetic engineering now being used commercially is in the agricultural sector. Plants are genetically engineered to be resistant to herbicides, to have built in pesticide resistance, and to convert nitrogen directly from the soil. Insects are being genetically engineered to attack crop predators. Research is ongoing in growing agricultural products directly in the laboratory using genetically engineered bacteria. Also envisioned is a major commercial role for genetically engineered plants as chemical factories. For example, organic plastics are already being produced in this manner.8

2) Genetically engineered animals are being developed as living factories for the production of pharmaceuticals and as sources of organs for transplantation into humans. (New animals created through the process of cross-species gene transfer are called xenographs. The transplanting of organs across species is called xenotransplantation.) A combination of genetic engineering and cloning is leading to the development of animals for meat with less fat, etc. Fish are being genetically engineered to grow larger and more rapidly.

3) Many pharmaceutical drugs, including insulin, are already genetically engineered in the laboratory. Many enzymes used in the food industry, including rennet used in cheese production, are also available in genetically engineered form and are in widespread use.

4) Medical researchers are genetically engineering disease carrying insects so that their disease potency is destroyed. They are genetically engineering human skin9 and soon hope to do the same with entire organs and other body parts.

5) Genetic screening is already used to screen for some hereditary conditions. Research is ongoing in the use of gene therapy in the attempt to correct some of these conditions. Other research is focusing on techniques to make genetic changes directly in human embryos. Most recently research has also been focused on combining cloning with genetic enginering. In so-called germline therapy, the genetic changes are passed on from generation to generation and are permanent.

6) In mining, genetically engineered organisms are being developed to extract gold, copper, etc. from the substances in which it is embedded. Other organisms may someday live on the methane gas that is a lethal danger to miners. Still others have been genetically engineered to clean up oil spills, to neutralize dangerous pollutants, and to absorb radioactivity. Genetically engineered bacteria are being developed to transform waste products into ethanol for fuel.

SOME DISTINGUISHED SCIENTISTS' OPINIONS

In the 1950's, the media was full of information about the great new scientific miracle that was going to make it possible to kill all of the noxious insects in the world, to wipe out insect-born diseases and feed the world's starving masses. That was DDT. In the 1990's, the media is full of information about the coming wonders of genetic engineering. Everywhere are claims that genetic engineering will feed the starving, help eliminate disease, and so forth. The question is the price tag. The ideas and evidence presented below are intended to help evaluate that central question.

Many prominent scientists have warned against the dangers of genetic engineering. George Wald, Nobel Prize-winning biologist and Harvard professor, wrote:

Recombinant DNA technology [genetic engineering] faces our society with problems unprecedented not only in the history of science, but of life on the Earth. It places in human hands the capacity to redesign living organisms, the products of some three billion years of evolution.

Such intervention must not be confused with previous intrusions upon the natural order of living organisms; animal and plant breeding, for example; or the artificial induction of mutations, as with X-rays. All such earlier procedures worked within single or closely related species. The nub of the new technology is to move genes back and forth, not only across species lines, but across any boundaries that now divide living organisms The results will be essentially new organisms. Self-perpetuating and hence permanent. Once created, they cannot be recalled

Up to now living organisms have evolved very slowly, and new forms have had plenty of time to settle in. Now whole proteins will be transposed overnight into wholly new associations, with consequences no one can foretell, either for the host organism or their neighbors.

It is all too big and is happening too fast. So this, the central problem, remains almost unconsidered. It presents probably the largest ethical problem that science has ever had to face. Our morality up to now has been to go ahead without restriction to learn all that we can about nature. Restructuring nature was not part of the bargain For going ahead in this direction may be not only unwise but dangerous. Potentially, it could breed new animal and plant diseases, new sources of cancer, novel epidemics.10

Erwin Chargoff, an eminent geneticist who is sometimes called the father of modern microbiology, commented:

The principle question to be answered is whether we have the right to put an additional fearful load on generations not yet born. I use the adjective 'additional' in view of the unresolved and equally fearful problem of the disposal of nuclear waste. Our time is cursed with the necessity for feeble men, masquerading as experts, to make enormously far-reaching decisions. Is there anything more far-reaching than the creation of forms of life? You can stop splitting the atom; you can stop visiting the moon; you can stop using aerosals; you may even decide not to kill entire populations by the use of a few bombs. But you cannot recall a new form of life. Once you have constructed a viable E. coli cell carry a plasmid DNA into which a piece of eukaryotic DNA has been spliced, it will survive you and your children and your children's children. An irreversible attack on the biosphere is something so unheard-of, so unthinkable to previous generations, that I could only wish that mine had not been guilty of it.11

It appears that the recombination experiments in which a piece of animal DNA is incorporated into the DNA of a microbial plasmid are being performed without a full appreciation of what is going on. Is the position of one gene with respect to its neighbors on the DNA chain accidental or do they control and regulate each other? Are we wise in getting ready to mix up what nature has kept apart, namely the genomes of eukaryotic and prokaryotic cells.

The worst is that we shall never know. Bacteria and viruses have always formed a most effective biological underground. The guerrilla warfare through which they act on higher forms of life is only imperfectly understood. By adding to this arsenal freakish forms of life-prokyarotes propagating eukaryotic genes-we shall be throwing a veil of uncertainties over the life of coming generations. Have we the right to counteract, irreversibly, the evolutionary wisdom of millions of years, in order to satisfy the ambition and curiosity of a few scientists?

This world is given to us on loan. We come and we go; and after a time we leave earth and air and water to others who come after us. My generation, or perhaps the one preceding mine, has been the first to engage, under the leadership of the exact sciences, in a destructive colonial warfare against nature. The future will curse us for it.12

In contrast, here are two examples of prominent scientists who support genetic engineering. Co-discoverer of the DNA code and Nobel Laureate Dr. James D. Watson takes this approach:

On the possible diseases created by recombinant DNA, Watson wrote in March 1979: 'I would not spend a penny trying to see if they exist' (Watson 1979:113). Watson's position is that we must go ahead until we experience serious disadvantages. We must take the risk of even a catastrophe that might be hidden in recombinant DNA technology. According to him that is how learning works: until a tiger devours you, you don't know that the jungle is dangerous.13

What is wrong with Watson's analogy? If Watson wants to go off into the jungle and put himself at risk of being eaten by a tiger, that is his business. What gives him the right to drag us all with him and put us at risk of being eaten? When genetically engineered organisms are released into the environment, they put us all at risk, not just their creators.

The above statement by a great scientist clearly shows that we cannot depend on the high priests of science to make our ethical decisions for us. Too much is at stake. Not all geneticists are so cavalier or unclear about the risks. Unfortunately the ones who see or care about the potential problems are in the minority. That is not really surprising, because many who did see some of the basic problems would either switch fields or not enter it in the first place. Many of those who are in it have found a fascinating playground, not only in which to earn a livelihood, but also one with high-stake prizes of fame and fortune.

Watson himself saw some of the problems clearly when he stated:

This [genetic engineering] is a matter far too important to be left solely in the hands of the scientific and medical communities. The belief thatscience always moves forward represents a form of laissez-faire nonsense dismally reminiscent of the credo that American business if left to itself will solve everybody's problems. Just as the success of a corporate body in making money need not set the human condition ahead, neither does every scientific advance automatically make our lives more 'meaningful'.14

Although not a geneticist, Stephen Hawking, the world-renowned physicist and cosmologist and Lucasian Professor of Mathematics at Cambridge University in England (a post once held by Sir Isaac Newton), has commented often and publicly on the future role of genetic engineering. For example:

Hawking, known mostly for his theories about the Big Bang and black holes, is focusing a lot these days on how humanity fits into the future of the universe--if indeed it fits at all. One possibility he suggests is that once an intelligent life form reaches the stage we're at now, it proceeds to destroy itself. He's an optimist, however, preferring the notion that people will alter DNA, redesigning the race to minimize our aggressive nature and give us a better chance at long-term survival. ``Humans will change their genetic makeup to give them more intelligence and better memory,'' he said.15

Hawking assumes that, even though humans are about to destroy themselves, they have the wisdom to know how to redesign themselves. If that were the case, why would we be about to destroy ourselves in the first place? Is Hawking assuming that genes control IQ and memory, and that they are equivalent to wisdom, or is Hawking claiming there is a wisdom gene? All these assumptions are extremely dubious. The whole notion that we can completely understand what it means to be human with a small part of our intellect, which is in turn a small part of who we are is, in its very nature, extremely suspect. If we attempt to transform ourselves in the image of a small part of ourselves, what we transform ourselves into will certainly be something smaller or at least a serious distortion of our human nature.

Those questions aside, Hawking does make explicit that, for the first time in history, natural evolution has come to an end and has been replaced by humans meddling with their own genetic makeup. With genetic engineering science has moved from exploring the natural world and its mechanisms to redesigning them. This is a radical departure in the notion of what we mean by science. As Nobel Prize winning biologist Professor George Wald was quoted above as saying: "Our morality up to now has been to go ahead without restriction to learn all that we can about nature. Restructuring nature was not part of the bargain."16

Hawking's views illustrate that even brilliant scientists, whose understanding of science should be impeccable, can get caught in the web of scientism. "Scientism"17 refers to the extending of science beyond the use of the scientific method and wrongly attempting to use it as the foundation for belief systems. Scientism promotes the myth that science is the sole source of truth about ourselves and the world we live in.

Most scientific research is dependent on artificial closed system models, yet the cosmos is an open system. Therefore, there are a priori limitations to the relevance of scientific data to the open system of the natural world. What seems to be the case in the laboratory may or may not be valid in the natural world.17a Therefore, we cannot know through scientific methodology the full extent of the possible effects of genetic alterations in living creatures.18

If science is understood in terms of hypotheses from data collected according to scientific method, then the claims of Hawking in the name of science extend far beyond what science actually is. He is caught in an unconscious web of presuppositions and values that deeply affect both his hypotheses and his interpretation of data. It is not only Hawking who is caught in this web but all of us, regardless of our philosophical positions, because scientism is part of our cultural background that is very hard to shake. We all have to keep in mind that there is more to the world than what our current crop of scientific instruments can detect.

Hawking's notions are at least altruistic. Perhaps more dangerous in the short run are projected commercial applications of so-called 'designer genes': gene alterations to change the physical appearance of our offspring to more closely match cultural values and styles. When we change the eye-color, height, weight, and other bodily characteristics of our offspring, how do we know what else is also being changed? Genes are not isolated units that have simple one-to-one correspondences.19

SOME SPECIFIC DIFFICULTIES WITH GENETIC ENGINEERING

Here are a few examples of current efforts in genetic engineering that may cause us to think twice about its rosy benefits.

The Potential of Genetic Engineering for Disrupting the Natural Ecosystems of the Biosphere

At a time when an estimated 50,000 species are already expected to become extinct every year, any further interference with the natural balance of ecosystems could cause havoc. Genetically engineered organisms, with their completely new and unnatural combinations of genes, have a unique power to disrupt our environment. Since they are living, they are capable of reproducing, mutating and moving within the environment. As these new life forms move into existing habitats they could destroy nature as we know it, causing long term and irreversible changes to our natural world.20

Any child who has had an aquarium knows that the fish, plants, snails, and food have to be kept in balance to keep the water clear and the fish healthy. Natural ecosystems are more complex but operate in a similar manner. Nature, whether we consider it to be conscious or without consciousness, is a self-organizing system with its own mechanisms.21 In order to guarantee the long-term viability of the system, those mechanisms insure that important equilibria are maintained. Lately the extremes of human environmental pollution and other human activities have been putting deep strains on those mechanisms. Nonetheless, just as we can clearly see when the aquarium is out of kilter, we can learn to sensitize ourselves to Nature's warnings and know when we are endangering Nature's mechanisms for maintaining equilibria. We can see an aquarium clearly. Unfortunately, because of the limitations of our senses in detecting unnatural and often invisible change, we may not become aware of serious dangers to the environment until widespread damage has already been done.

Deep ecology22 and Gaia theory have brought to general awareness the interactive and interdependent quality of environmental systems.22a No longer do we believe that isolated events occur in nature. Each event is part of a vast web of inter-causality, and as such has widespread consequences within that ecosystem.

If we accept the notion that the biosphere has its own corrective mechanisms, then we have to look at how they work and the limitations of their design. The more extreme the disruption to the self-organizing systems of the biosphere, the stronger the corrective measures are necessary. The notion that the systems can ultimately deal with any threat, however extreme, is without scientific basis. No evidence exists that the life and welfare of human beings have priority in those self-organizing systems. Nor does any evidence exist that anything in those systems is equipped to deal with all the threats that genetically engineered organisms may pose. Why? The organisms are not in the experience of the systems, because they could never occur naturally as a threat. The basic problem is a denial on the part of many geneticists that genetically engineered organisms are radical, new, and unnatural forms of life, which, as such, have no place in the evolutionarily balanced biosphere.

Viruses

Plant, animal and human viruses play a major role in the ecosystems that comprise the biosphere. They are thought by some to be one of the primary factors in evolutionary change. Viruses have the ability to enter the genetic material of their hosts, to break apart, and then to recombine with the genetic material of the host to create new viruses. Those new viruses then infect new hosts, and, in the process, transfer new genetic material to the new host. When the host reproduces, genetic change has occurred.

If cells are genetically engineered, when viruses enter the cells, whether human, animal, or plant, then some of the genetically engineered material can be transferred to the newly created viruses and spread to the viruses' new hosts. We can assume that ordinary viruses, no matter how deadly, if naturally produced, have a role to play in an ecosystem and are regulated by that ecosystem. Difficulties can occur when humans carry them out of their natural ecosystems; nonetheless, all ecosystems in the biosphere may presumably share certain defense characteristics. Since viruses that contain genetically engineered material could never naturally arise in an ecosystem, there is no guarantee of natural defenses against them. They then can lead to widespread death of humans, animals or plants, thereby temporarily or even permanently damaging the ecosystem. Widespread die-off of a plant species is not an isolated event but can affect its whole ecosystem. For many, this may be a rather theoretical concern. The distinct possibility of the widespread die-off of human beings from genetically engineered viruses may command more attention.23

Biowarfare

Secret work is going forward in many countries to develop genetically engineered bacteria and viruses for biological warfare. International terrorists have already begun seriously considering their use. They are almost impossible to regulate, because the same equipment and technology that are used commercially can easily and quickly be transferred to military application.

The former Soviet Union had 32,000 scientists working on biowarfare, including military applications of genetic engineering. No one knows where most of them have gone, or what they have taken with them. Among the more interesting probable developments of their research were smallpox viruses engineered either with equine encephalitis or with Ebola virus. In one laboratory, despite the most stringent containment standards, a virulent strain of pneumonia, which had been stolen from the United State military, infected wild rats living in the building, which then escaped into the wild.24

There is also suggestive evidence that much of the so-called Gulf War Syndrome may have been caused by a genetically engineered biowarfare agent which is contagious after a relatively long incubation period. Fortunately that particular organism seems to respond to antibiotic treatment.25 What is going to happen when the organisms are purposely engineered to resist all known treatment?

Nobel laureate in genetics and president emeritus of Rockefeller University Joshua Lederberg has been in the forefront of those concerned about international control of biological weapons. Yet when I wrote Dr. Lederberg for information about ethical problems in the use of genetic engineering in biowarfare, he replied, "I don't see how we'd be talking about the ethics of genetic engineering, any more than that of iron smelting - which can be used to build bridges or guns."26 Like most scientists, Lederberg fails to acknowledge that scientific researchers have a responsibility for the use to which their discoveries are put. Thus he also fails to recognize that once the genie is out of the bottle, you cannot coax it back in. In other words, research in genetic engineering naturally leads to its employment for biowarfare, so that before any research in genetic engineering is undertaken, its potential use in biowarfare should be clearly evaluated. After they became aware of the horrors of nuclear war, many of the scientists who worked in the Manhattan project, which developed the first atomic bomb, underwent terrible anguish and soul-searching. It is surprising that more geneticists do not see the parallels.

After reading about the dangers of genetic engineering in biowarfare, the president of the United States, Bill Clinton, became extremely concerned, and, in the spring of 1998, made civil defense countermeasures a priority. Yet, his administration has systematically opposed all but the most rudimentary safety regulations and restrictions for the biotech industry. By doing so, Clinton has unwittingly created a climate in which the production of the weapons he is trying to defend against has become very easy for both governments and terrorists.27

Plants

New crops may breed with wild relatives or cross breed with related species. The "foreign" genes could spread throughout the environment causing unpredicted changes which will be unstoppable once they have begun. Entirely new diseases may develop in crops or wild plants. Foreign genes are designed to be carried into other organisms by viruses which can break through species barriers, and overcome an organism's natural defenses. This makes them more infectious than naturally existing parasites, so any new viruses could be even more potent than those already known.

Ordinary weeds could become "Super-weeds": Plants engineered to be herbicide resistant could become so invasive they are a weed problem themselves, or they could spread their resistance to wild weeds making them more invasive. Fragile plants may be driven to extinction, reducing nature's precious biodiversity. Insects could be impossible to control. Making plants resistant to chemical poisons could lead to a crisis of "super pests" if they also take on the resistance to pesticides.

The countryside may suffer even greater use of herbicides and pesticides: Because farmers will be able to use these toxic chemicals with impunity their use may increase threatening more pollution of water supplies and degradation of soils.

Plants developed to produce their own pesticide could harm non-target species such as birds, moths and butterflies. No one - including the genetic scientists - knows for sure the effect releasing new life forms will have on the environment. They do know that all of the above are possible and irreversible, but they still want to carry out their experiment. THEY get giant profits. All WE get is a new and uncertain environment - an end to the world as we know it.29

When genetically engineered crops are grown for a specific purpose, they cannot be easily isolated both from spreading into the wild and from cross-pollinating with wild relatives. It has already been shown30 that cross-pollination can take place almost a mile away from the genetically engineered plantings. As has already occurred with noxious weeds and exotics, human beings, animals and birds may accidentally carry the genetically engineered seeds far vaster distances. Spillage in transport and at processing factories is also inevitable. The genetically engineered plants can then force out plant competitors and thus radically change the balance of ecosystems or even destroy them.

Under current United States government regulations, companies that are doing field-testing of genetically engineered organisms need not inform the public of what genes have been added to the organisms they are testing. They can be declared trade secrets, so that the public safety is left to the judgment of corporate scientists and government regulators many of whom switch back and forth between working for the government and working for the corporations they supposedly regulate.31 Those who come from academic positions often have large financial stakes in biotech companies, 32 and major universities are making agreements with biotech corporations that compromise academic freedom and give patent rights to the corporations. As universities become increasingly dependent on major corporations for funding, the majority of university scientists will no longer be able to function as independent, objective experts in matters concerning genetic engineering and public safety.32a

Scientists have already demonstrated the transfer of transgenes and marker genes to both bacterial pathogens and to soil fungi. That means genetically engineered organisms are going to enter the soil and spread to whatever grows in it. Genetically engineered material can migrate from the roots of plants into soil bacteria, in at least one case radically inhibiting the ability of the soil to grow plants.33 Once the bacteria are free in the soil, no natural barriers inhibit their spread. With ordinary soil pollution, the pollution can be confined and removed (unless it reaches the ground-water). If genetically engineered soil bacteria spreads into the wild, the ability of the soil to support plant life may seriously diminish.33a It does not take much imagination to see what the disastrous consequences might be.

Water and air are also subject to poisoning by genetically engineered viruses and bacteria.

The development of new genetically engineered crops with herbicide resistance will affect the environment through the increased use of chemical herbicides. Monsanto and other major international chemical, pharmaceutical, and agricultural corporations have staked their financial futures on genetically engineered herbicide-resistant plants.33b

Recently scientists have found a way to genetically engineer plants so that their seeds lose their viability unless sprayed with patented formulae, most of which turn out to have antibiotics as their primary ingredient. The idea is to keep farmers from collecting genetically engineered seed, thus forcing them to buy it every year. The corporations involved are unconcerned about the gene escaping into the wild, with obvious disastrous results, even though that is a clear scientific possibility.34

So that we would not have to be dependent on petroleum-based plastics, some scientists have genetically engineered plants that produce plastic within their stem structures. They claim that it biodegrades in about six months.35 If the genes escape into the wild, through cross-pollination with wild relatives or by other means, then we face the prospect of natural areas littered with the plastic spines of decayed leaves. However aesthetically repugnant that may seem, the plastic also poses a real danger. It has the potential for disrupting entire food-chains. It can be eaten by invertebrates, which are in turn eaten, and so forth. If primary foods are inedible or poisonous, then whole food-chains can die off.36

Another bright idea was to genetically engineer plants with scorpion toxin, so that insects feeding on the plants would be killed. Even though a prominent geneticist warned that the genes could be horizontally transferred to the insects themselves, so that they might be able to inject the toxin into humans, the research and field testing is continuing.37

Animals

The genetic engineering of new types of insects, fish, birds and animals has the potential of upsetting natural ecosystems. They can displace natural species and upset the balance of other species through behavior patterns that are a result of their genetic transformation.

One of the more problematic ethical uses of animals is the creation of xenographs, already mentioned above, which often involve the insertion of human genes. (See the section immediately below.) Whether or not the genes inserted to create new animals are human ones, the xenographs are created for human use and patented for corporate profit with little or no regard for the suffering of the animals, their felings and thoughts, or their natural life-patterns.

Use of Human Genes

As more and more human genes are being inserted into non-human organisms to create new forms of life that are genetically partly human, new ethical questions arise. What percent of human genes does an organism have to contain before it is considered human? For instance, how many human genes would a green pepper38 have to contain before one would have qualms about eating it? For meat-eaters, the same question could be posed about eating pork. If human beings have special ethical status, does the presence of human genes in an organism change its ethical status? What about a mouse genetically engineered to produce human sperm39 that is then used in the conception of a human child?

Several companies are working on developing pigs that have organs containing human genes in order to facilitate the use of the organs in humans. The basic idea is something like this. You can have your own personal organ donor pig with your genes implanted. When one of your organs gives out, you can use the pig's.

The U.S. Food and Drug Administration (FDA) issued a set of xenotransplant guidelines in September of 1996 that allows animal to human transplants, and puts the responsibility for health and safety at the level of local hospitals and medical review boards. A group of 44 top virologists, primate researchers, and AIDS specialists have attacked the FDA guidelines, saying, "based on knowledge of past cross-species transmissions, including AIDS, Herpes B virus, Ebola, and other viruses, the use of animals has not been adequately justified for use in a handful of patients when the potential costs could be in the hundreds, thousands or millions of human lives should a new infectious agent be transmitted."40

England has outlawed such transplants as too dangerous.41

Humans

Genetically engineered material can enter the body through food or bacteria or viruses. The dangers of lethal viruses containing genetically engineered material and created by natural processes have been mentioned above.

The dangers of generating pathogens by vector mobilization and recombination are real. Over a period of ten years, 6 scientists working with the genetic engineering of cancer-related oncogenes at the Pasteur Institutes in France have contracted cancer.42

Non-human engineered genes can also be introduced into the body through the use of genetically engineered vaccines and other medicines, and through the use of animal parts genetically engineered with human genes to combat rejection problems.

Gene therapy, for the correction of defective human genes that cause certain genetic diseases, involves the intentional introduction of new genes into the body in an attempt to modify the genetic structure of the body. It is based on a simplistic and flawed model of gene function which assumes a one-to-one correspondence between individual gene and individual function. Since horizontal interaction43 among genes has been demonstrated, introduction of a new gene can have unforeseen effects. Another problem, already mentioned, is the slippery slope that leads to the notion of designer genes. We are already on that slope with the experimental administration of genetically engineered growth hormone to healthy children, simply because they are shorter than average and their parents would like them to be taller.44

A few years ago a biotech corporation applied to the European Patent Office for a patent on a so-called 'pharm-woman,' the idea being to genetically engineer human females so that their breast-milk would contain specialized pharmaceuticals.44a Work is also ongoing to use genetic engineering to grow human breasts in the laboratory. It doesn't take much imagination to realize that not only would they be used for breast replacement needed due to cancer surgery, but also to foster a vigorous commercial demand by women in search of the "perfect" breasts.45 A geneticist has recently proposed genetically engineering headless humans to be used for body parts. Some prominent geneticists have supported his idea.46

Genetically Engineered Food

Many scientists have claimed that the ingestion of genetically engineered food is harmless because the genetically engineered materials are destroyed by stomach acids. Recent research47 suggests that genetically engineered materials are not completely destroyed by stomach acids and that significant portions reach the bloodstream and also the brain-cells. Furthermore, it has been shown that the natural defense mechanisms of body cells are not entirely effective in keeping the genetically engineered substances out of the cells.48

Some dangers of eating genetically engineered foods are already documented. Risks to human health include the probable increase in the level of toxins in foods and in the number of disease-causing organisms that are resistant to antibiotics.49 The purposeful increase in toxins in foods to make them insect-resistant is the reversal of thousands of years of selective breeding of food-plants. For example when plants are genetically engineered to resist predators, often the plant defense systems involve the synthesis of natural carcinogens.50

Industrial mistakes or carelessness in production of genetically engineered food ingredients can also cause serious problems. The l-tryptophan food supplement, an amino acid that was marketed as a natural tranquilizer and sleeping pill, was genetically engineered. It killed thirty-seven people and permanently disabled 1,500 others with an incurable nervous system condition known as eosinophilia myalgia syndrome (EMS).51

Dr. John Fagan has summarized some major risks of eating genetically engineered food as follows:

the new proteins produced in genetically engineered foods could: a) themselves, act as allergens or toxins, b) alter the metabolism of the food producing organism, causing it to produce new allergens or toxins, or c) causing it to be reduced in nutritional value.a) Mutations can damage genes naturally present in the DNA of an organism, leading to altered metabolism and to the production of toxins, and to reduced nutritional value of the food. b) Mutations can alter the expression of normal genes, leading to the production of allergens and toxins, and to reduced nutritional value of the food. c) Mutations can interfere with other essential, but yet unknown, functions of an organisms DNA.52

Basically what we have at present is a situation in which genetically engineered foods are beginning to flood the market, and no one knows what all their effects on humans will be. We are all becoming guinea pigs. Because genetically engineered food remains unlabeled, should serious problems arise, it will be extremely difficult to trace them to their source. Lack of labeling will also help to shield the corporations that are responsible from liability.

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Genetic Engineering – BiologyMad

Wednesday, September 30th, 2015

Genetic Engineering

Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a Genetically Modified Organism (GMO) with a new genotype. Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all.

Genetic engineering is a very young discipline, and is only possible due to the development of techniques from the 1960s onwards. Watson and Crick have made these techniques possible from our greater understanding of DNA and how it functions following the discovery of its structure in 1953. Although the final goal of genetic engineering is usually the expression of a gene in a host, in fact most of the techniques and time in genetic engineering are spent isolating a gene and then cloning it. This table lists the techniques that we shall look at in detail.

1

cDNA

To make a DNA copy of mRNA

2

To cut DNA at specific points, making small fragments

3

DNA Ligase

To join DNA fragments together

4

Vectors

To carry DNA into cells and ensure replication

5

Plasmids

Common kind of vector

6

Gene Transfer

To deliver a gene to a living cells

7

Genetic Markers

To identify cells that have been transformed

8

To make exact copies of bacterial colonies on an agar plate

9

PCR

To amplify very small samples of DNA

10

DNA probes

To identify and label a piece of DNA containing a certain sequence

11

Shotgun *

To find a particular gene in a whole genome

12

Antisense genes *

To stop the expression of a gene in a cell

13

Gene Synthesis

To make a gene from scratch

14

Electrophoresis

To separate fragments of DNA

* Additional information that is not directly included in AS Biology. However it can help to consolidate other techniques.

Complementary DNA (cDNA) is DNA made from mRNA. This makes use of the enzyme reverse transcriptase, which does the reverse of transcription: it synthesises DNA from an RNA template. It is produced naturally by a group of viruses called the retroviruses (which include HIV), and it helps them to invade cells. In genetic engineering reverse transcriptase is used to make an artificial gene of cDNA as shown in this diagram.

Complementary DNA has helped to solve different problems in genetic engineering:

It makes genes much easier to find. There are some 70 000 genes in the human genome, and finding one gene out of this many is a very difficult (though not impossible) task. However a given cell only expresses a few genes, so only makes a few different kinds of mRNA molecule. For example the b cells of the pancreas make insulin, so make lots of mRNA molecules coding for insulin. This mRNA can be isolated from these cells and used to make cDNA of the insulin gene.

These are enzymes that cut DNA at specific sites. They are properly called restriction endonucleases because they cut the bonds in the middle of the polynucleotide chain. Some restriction enzymes cut straight across both chains, forming blunt ends, but most enzymes make a staggered cut in the two strands, forming sticky ends.

The cut ends are sticky because they have short stretches of single-stranded DNA with complementary sequences. These sticky ends will stick (or anneal) to another piece of DNA by complementary base pairing, but only if they have both been cut with the same restriction enzyme. Restriction enzymes are highly specific, and will only cut DNA at specific base sequences, 4-8 base pairs long, called recognition sequences.

Restriction enzymes are produced naturally by bacteria as a defence against viruses (they restrict viral growth), but they are enormously useful in genetic engineering for cutting DNA at precise places ("molecular scissors"). Short lengths of DNA cut out by restriction enzymes are called restriction fragments. There are thousands of different restriction enzymes known, with over a hundred different recognition sequences. Restriction enzymes are named after the bacteria species they came from, so EcoR1 is from E. coli strain R, and HindIII is from Haemophilis influenzae.

This enzyme repairs broken DNA by joining two nucleotides in a DNA strand. It is commonly used in genetic engineering to do the reverse of a restriction enzyme, i.e. to join together complementary restriction fragments.

The sticky ends allow two complementary restriction fragments to anneal, but only by weak hydrogen bonds, which can quite easily be broken, say by gentle heating. The backbone is still incomplete.

DNA ligase completes the DNA backbone by forming covalent bonds. Restriction enzymes and DNA ligase can therefore be used together to join lengths of DNA from different sources.

In biology a vector is something that carries things between species. For example the mosquito is a disease vector because it carries the malaria parasite into humans. In genetic engineering a vector is a length of DNA that carries the gene we want into a host cell. A vector is needed because a length of DNA containing a gene on its own wont actually do anything inside a host cell. Since it is not part of the cells normal genome it wont be replicated when the cell divides, it wont be expressed, and in fact it will probably be broken down pretty quickly. A vector gets round these problems by having these properties:

It is big enough to hold the gene we want (plus a few others), but not too big.

It is circular (or more accurately a closed loop), so that it is less likely to be broken down (particularly in prokaryotic cells where DNA is always circular).

It contains control sequences, such as a replication origin and a transcription promoter, so that the gene will be replicated, expressed, or incorporated into the cells normal genome.

It contain marker genes, so that cells containing the vector can be identified.

Many different vectors have been made for different purposes in genetic engineering by modifying naturally-occurring DNA molecules, and these are now available off the shelf. For example a cloning vector contains sequences that cause the gene to be copied (perhaps many times) inside a cell, but not expressed. An expression vector contains sequences causing the gene to be expressed inside a cell, preferably in response to an external stimulus, such as a particular chemical in the medium. Different kinds of vector are also available for different lengths of DNA insert:

Type of vector

Max length of DNA insert

10 kbp

Virus or phage

30 kbp

Bacterial Artificial Chromosome (BAC)

500 kbp

Plasmids are by far the most common kind of vector, so we shall look at how they are used in some detail. Plasmids are short circular bits of DNA found naturally in bacterial cells. A typical plasmid contains 3-5 genes and there are usually around 10 copies of a plasmid in a bacterial cell. Plasmids are copied separately from the main bacterial DNA when the cell divides, so the plasmid genes are passed on to all daughter cells. They are also used naturally for exchange of genes between bacterial cells (the nearest they get to sex), so bacterial cells will readily take up a plasmid. Because they are so small, they are easy to handle in a test tube, and foreign genes can quite easily be incorporated into them using restriction enzymes and DNA ligase.

One of the most common plasmids used is the R-plasmid (or pBR322). This plasmid contains a replication origin, several recognition sequences for different restriction enzymes (with names like PstI and EcoRI), and two marker genes, which confer resistance to different antibiotics (ampicillin and tetracycline).

The diagram below shows how DNA fragments can be incorporated into a plasmid using restriction and ligase enzymes. The restriction enzyme used here (PstI) cuts the plasmid in the middle of one of the markergenes (well see why this is useful later). The foreign DNA anneals with the plasmid and is joined covalently by DNA ligase to form a hybrid vector (in other words a mixture or hybrid of bacterial and foreign DNA). Several other products are also formed: some plasmids will simply re-anneal with themselves to re-form the original plasmid, and some DNA fragments will join together to form chains or circles. Theses different products cannot easily be separated, but it doesnt matter, as the marker genes can be used later to identify the correct hybrid vector.

Vectors containing the genes we want must be incorporated into living cells so that they can be replicated or expressed. The cells receiving the vector are called host cells, and once they have successfully incorporated the vector they are said to be transformed. Vectors are large molecules which do not readily cross cell membranes, so the membranes must be made permeable in some way. There are different ways of doing this depending on the type of host cell.

Heat Shock. Cells are incubated with the vector in a solution containing calcium ions at 0C. The temperature is then suddenly raised to about 40C. This heat shock causes some of the cells to take up the vector, though no one knows why. This works well for bacterial and animal cells.

Electroporation. Cells are subjected to a high-voltage pulse, which temporarily disrupts the membrane and allows the vector to enter the cell. This is the most efficient method of delivering genes to bacterial cells.

Viruses. The vector is first incorporated into a virus, which is then used to infect cells, carrying the foreign gene along with its own genetic material. Since viruses rely on getting their DNA into host cells for their survival they have evolved many successful methods, and so are an obvious choice for gene delivery. The virus must first be genetically engineered to make it safe, so that it cant reproduce itself or make toxins. Three viruses are commonly used:

1. Bacteriophages (or phages) are viruses that infect bacteria. They are a very effective way of delivering large genes into bacteria cells in culture.

2. Adenoviruses are human viruses that causes respiratory diseases including the common cold. Their genetic material is double-stranded DNA, and they are ideal for delivering genes to living patients in gene therapy. Their DNA is not incorporated into the hosts chromosomes, so it is not replicated, but their genes are expressed.

The adenovirus is genetically altered so that its coat proteins are not synthesised, so new virus particles cannot be assembled and the host cell is not killed.

3. Retroviruses are a group of human viruses that include HIV. They are enclosed in a lipid membrane and their genetic material is double-stranded RNA. On infection this RNA is copied to DNA and the DNA is incorporated into the hosts chromosome. This means that the foreign genes are replicated into every daughter cell.

After a certain time, the dormant DNA is switched on, and the genes are expressed in all the host cells.

Plant Tumours. This method has been used successfully to transform plant cells, which are perhaps the hardest to do. The gene is first inserted into the Ti plasmid of the soil bacterium Agrobacterium tumefaciens, and then plants are infected with the bacterium. The bacterium inserts the Ti plasmid into the plant cells' chromosomal DNA and causes a "crown gall" tumour. These tumour cells can be cultured in the laboratory and whole new plants grown from them by micropropagation. Every cell of these plants contains the foreign gene.

Gene Gun. This extraordinary technique fires microscopic gold particles coated with the foreign DNA at the cells using a compressed air gun. It is designed to overcome the problem of the strong cell wall in plant tissue, since the particles can penetrate the cell wall and the cell and nuclear membranes, and deliver the DNA to the nucleus, where it is sometimes expressed.

Micro-Injection. A cell is held on a pipette under a microscope and the foreign DNA is injected directly into the nucleus using an incredibly fine micro-pipette. This method is used where there are only a very few cells available, such as fertilised animal egg cells. In the rare successful cases the fertilised egg is implanted into the uterus of a surrogate mother and it will develop into a normal animal, with the DNA incorporated into the chromosomes of every cell.

Liposomes. Vectors can be encased in liposomes, which are small membrane vesicles (see module 1). The liposomes fuse with the cell membrane (and sometimes the nuclear membrane too), delivering the DNA into the cell. This works for many types of cell, but is particularly useful for delivering genes to cell in vivo (such as in gene therapy).

These are needed to identify cells that have successfully taken up a vector and so become transformed. With most of the techniques above less than 1% of the cells actually take up the vector, so a marker is needed to distinguish these cells from all the others. Well look at how to do this with bacterial host cells, as thats the most common technique.

A common marker, used in the R-plasmid, is a gene for resistance to an antibiotic such as tetracycline. Bacterial cells taking up this plasmid can make this gene product and so are resistant to this antibiotic. So if the cells are grown on a medium containing tetracycline all the normal untransformed cells, together with cells that have taken up DNA thats not in a plasmid (99%) will die. Only the 1% transformed cells will survive, and these can then be grown and cloned on another plate.

Replica plating is a simple technique for making an exact copy of an agar plate. A pad of sterile cloth the same size as the plate is pressed on the surface of an agar plate with bacteria growing on it. Some cells from each colony will stick to the cloth. If the cloth is then pressed onto a new agar plate, some cells will be deposited and colonies will grow in exactly the same positions on the new plate. This technique has a number of uses, but the most common use in genetic engineering is to help solve another problem in identifying transformed cells.

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Genetic Engineering – HowStuffWorks

Monday, September 7th, 2015

Genetic Engineering, the process of extracting DNA (deoxyribonucleic acid, which makes up the genes of all living things) from one organism and combining it with the DNA of another organism, thus introducing new hereditary traits into the recipient organism. The nature and characteristics of every living creature is determined by the special combinations of genes carried by its cells. The slightest alteration in these combinations can bring about significant changes in an organism and also its progeny. The science of devising techniques of modifying or controlling genes and genetic combinations is referred to as genetic engineering. It was practiced in one form or another in the past by farmers and agriculturists trying to create economically viable species of plants and animals through various breeding techniques Genetic engineering, as a science, was developed in the mid-1970's primarily to create new strains of microorganisms that produce certain chemicals useful in manufacturing or as drugs. Genetic engineering is now also applied to improving plants and creating transgenic animals (animals containing foreign genetic material).

Some persons oppose genetic engineering on religious, ethical, or social grounds. Among the religious questions is whether humans have the right to transfer traits from one organism to another. A social concern is the possibility of creating harmful organisms that, if accidentally released into the environment, could cause epidemics.The creation of human clones, for example, is facing serious opposition especially on moral grounds. Organizations, such as the National Institutes of Health (NIH), are seeking to control the harmful effects of genetic engineering by imposing guidelines and safety measures for genetic experimentation. Treatment of hereditary defects through gene transplantation and controlled interchange of genes between specified species was approved in 1985 and 1987 respectively by the NIH and the National Academy of Sciences. The USDA has framed regulations for the genetic alteration of plants by plant breeders.

The U.S. Supreme Court ruled in 1980 that genetically engineered microorganisms could be patented. In 1988 the U.S. Patent and Trademark Office issued its first patent for a higher form of life, a transgenic mouse that is highly susceptible to certain cancers that appear frequently in humans. This mouse is used in cancer research.

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Interactives . DNA . Genetic Engineering

Monday, August 3rd, 2015

Genetic engineering is the process of removing a gene from one organism and putting it into another. Often, the removed genes are put into bacteria or yeast cells so that scientists can study the gene or the protein it produces more easily. Sometimes, genes are put into a plant or an animal.

One of the first genetic engineering advances involved the hormone insulin. Diabetes, a medical condition that affects millions of people, prevents the body from producing enough insulin necessary for cells to properly absorb sugar. Diabetics used to be treated with supplementary insulin isolated from pigs or cows. Although this insulin is very similar to human insulin, it is not identical. Bovine insulin is antigenic in humans. Antibodies produced against it would gradually destroy its efficacy.

Scientists got around the problem by putting the gene for human insulin into bacteria. The bacteria's cellular machinery, which is identical to the cellular machinery of all living things, "reads" the gene, and turns it into a protein-human insulin-through a process called translation.

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genetic engineering | Britannica.com

Saturday, July 18th, 2015

genetic engineering,the artificial manipulation, modification, and recombination of DNA or other nucleic acid molecules in order to modify an organism or population of organisms.

The term genetic engineering initially meant any of a wide range of techniques for the modification or manipulation of organisms through the processes of heredity and reproduction. As such, the term embraced both artificial selection and all the interventions of biomedical techniques, among them artificial insemination, in vitro fertilization (e.g., test-tube babies), sperm banks, cloning, and gene manipulation. But the term now denotes the narrower field of recombinant DNA technology, or gene cloning (see Figure), in which DNA molecules from two or more sources are combined either within cells or in vitro and are then inserted into host organisms in which they are able to propagate. Gene cloning is used to produce new genetic combinations that are of value to science, medicine, agriculture, or industry.

DNA is the carrier of genetic information; it achieves its effects by directing the synthesis of proteins. Most recombinant DNA technology involves the insertion of foreign genes into the plasmids of common laboratory strains of bacteria. Plasmids are small rings of DNA; they are not part of the bacteriums chromosome (the main repository of the organisms genetic information). Nonetheless, they are capable of directing protein synthesis, and, like chromosomal DNA, they are reproduced and passed on to the bacteriums progeny. Thus, by incorporating foreign DNA (for example, a mammalian gene) into a bacterium, researchers can obtain an almost limitless number of copies of the inserted gene. Furthermore, if the inserted gene is operative (i.e., if it directs protein synthesis), the modified bacterium will produce the protein specified by the foreign DNA.

A key step in the development of genetic engineering was the discovery of restriction enzymes in 1968 by the Swiss microbiologist Werner Arber. However, type II restriction enzymes, which are essential to genetic engineering for their ability to cleave a specific site within the DNA (as opposed to type I restriction enzymes, which cleave DNA at random sites), were not identified until 1969, when the American molecular biologist Hamilton O. Smith purified this enzyme. Drawing on Smiths work, the American molecular biologist Daniel Nathans helped advance the technique of DNA recombination in 197071 and demonstrated that type II enzymes could be useful in genetic studies. Genetic engineering itself was pioneered in 1973 by the American biochemists Stanley N. Cohen and Herbert W. Boyer, who were among the first to cut DNA into fragments, rejoin different fragments, and insert the new genes into E. coli bacteria, which then reproduced.

Genetic engineering has advanced the understanding of many theoretical and practical aspects of gene function and organization. Through recombinant DNA techniques, bacteria have been created that are capable of synthesizing human insulin, human growth hormone, alpha interferon, a hepatitis B vaccine, and other medically useful substances. Plants may be genetically adjusted to enable them to fix nitrogen, and genetic diseases can possibly be corrected by replacing bad genes with normal ones. Nevertheless, special concern has been focused on such achievements for fear that they might result in the introduction of unfavourable and possibly dangerous traits into microorganisms that were previously free of theme.g., resistance to antibiotics, production of toxins, or a tendency to cause disease.

The new microorganisms created by recombinant DNA research were deemed patentable in 1980, and in 1986 the U.S. Department of Agriculture approved the sale of the first living genetically altered organisma virus, used as a pseudorabies vaccine, from which a single gene had been cut. Since then several hundred patents have been awarded for genetically altered bacteria and plants.

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Genetic engineering: a guide for kids by Tiki the Penguin

Monday, July 6th, 2015

Genetic engineering (GE for short) is about scientists altering the 'recipes' for making life the genes which you find in all living things. Doing this is very clever and seems to be very useful. Back in the 1990s, many 'Greens' campaigned against genetic engineering and still do. They predicted disaster but that hasn't happened. Nobody has died from eating genetically modified (GM) food. They were also worried about the private GE companies' ownership of the recipes genes for making these new life forms. So is genetic engineering okay? My guide explains the basics but it's up to you to make up your own mind about GE.

Finding your way around my GE Guide You can jump to any part that interests you from the table below. If you want to start at the beginning, click the green arrow below (forward to 'Genes, snails and whales').

Table of contents

Genes, snails and whales What makes you human or me a penguin? What are genes?

Tried and tested Life on Earth has been around for a long time so it's been well tested.

Adapt or die Only the fittest life survives. Here's how it does it.

Coils and corkscrews About that incredible stuff DNA.

Copycat: How DNA copies itself.

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What is genetic engineering? – Definition from WhatIs.com

Friday, July 3rd, 2015

Genetic engineering is the deliberate, controlled manipulation of the genes in an organism with the intent of making that organism better in some way. This is usually done independently of the natural reproductive process. The result is a so-called genetically modified organism (GMO). To date, most of the effort in genetic engineering has been focused on agriculture.

Proponents of genetic engineering claim that it has numerous benefits, including the production of food-bearing plants that are resistant to extreme weather and adverse climates, insect infestations, disease, molds, and fungi. In addition, it may be possible to reduce the amount of plowing necessary in the farming process, thereby saving energy and minimizing soil erosion. A major motivation is the hope of producing abundant food at low cost to reduce world hunger, both directly (by feeding GMOs to human beings) and indirectly (by feeding GMOs to livestock and fish, which can in turn be fed to humans).

Genetic engineering carries potential dangers, such as the creation of new allergens and toxins, the evolution of new weeds and other noxious vegetation, harm to wildlife, and the creation of environments favorable to the proliferation of molds and fungi (ironically, in light of the purported advantage in that respect). Some scientists have expressed concern that new disease organisms and increased antibiotic resistance could result from the use of GMOs in the food chain.

The darkest aspect of genetic engineering is the possibility that a government or institution might undertake to enhance human beings by means of genetic engineering. Some see the possibility of using this technology to create biological weapons.

Genetic engineering is also known as genetic modification.

This was last updated in May 2007

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Genetic Engineering – humans, body, used, process, plants …

Thursday, July 2nd, 2015

Photo by: Gernot Krautberger

Genetic engineering is any process by which genetic material (the building blocks of heredity) is changed in such a way as to make possible the production of new substances or new functions. As an example, biologists have now learned how to transplant the gene that produces light in a firefly into tobacco plants. The function of that genethe production of lighthas been added to the normal list of functions of the tobacco plants.

Genetic engineering became possible only when scientists had discovered exactly what is a gene. Prior to the 1950s, the term gene was used to stand for a unit by which some genetic characteristic was transmitted from one generation to the next. Biologists talked about a "gene" for hair color, although they really had no idea as to what that gene was or what it looked like.

That situation changed dramatically in 1953. The English chemist Francis Crick (1916 ) and the American biologist James Watson (1928 ) determined a chemical explanation for a gene. Crick and Watson discovered the chemical structure for large, complex molecules that occur in the nuclei of all living cells, known as deoxyribonucleic acid (DNA).

DNA molecules, Crick and Watson announced, are very long chains or units made of a combination of a simple sugar and a phosphate group.

Amino acid: An organic compound from which proteins are made.

DNA (deoxyribonucleic acid): A large, complex chemical compound that makes up the core of a chromosome and whose segments consist of genes.

Gene: A segment of a DNA molecule that acts as a kind of code for the production of some specific protein. Genes carry instructions for the formation, functioning, and transmission of specific traits from one generation to another.

Gene splicing: The process by which genes are cut apart and put back together to provide them with some new function.

Genetic code: A set of nitrogen base combinations that act as a code for the production of certain amino acids.

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