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see Genetic engineering

Snippet from Wikipedia: Genetically modified organism

A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with the most common being an organism altered in a way that "does not occur naturally by mating and/or natural recombination". A wide variety of organisms have been genetically modified (GM), from animals to plants and microorganisms. Genes have been transferred within the same species, across species (creating transgenic organisms) and even across kingdoms. New genes can be introduced, or endogenous genes can be enhanced, altered or knocked out.

Creating a genetically modified organism is a multi-step process. Genetic engineers must isolate the gene they wish to insert into the host organism and combine it with other genetic elements, including a promoter and terminator region and often a selectable marker. A number of techniques are available for inserting the isolated gene into the host genome. Recent advancements using genome editing techniques, notably CRISPR, have made the production of GMO's much simpler. Herbert Boyer and Stanley Cohen made the first genetically modified organism in 1973, a bacteria resistant to the antibiotic kanamycin. The first genetically modified animal, a mouse, was created in 1974 by Rudolf Jaenisch, and the first plant was produced in 1983. In 1994 the Flavr Savr tomato was released, the first commercialized genetically modified food. The first genetically modified animal to be commercialized was the GloFish (2003) and the first genetically modified animal to be approved for food use was the AquAdvantage salmon in 2015.

Bacteria are the easiest organisms to engineer and have been used for research, food production, industrial protein purification (including drugs), agriculture, and art. There is potential to use them for environmental, purposes or as medicine. Fungi have been engineered with much the same goals. Viruses play an important role as vectors for inserting genetic information into other organisms. This use is especially relevant to human gene therapy. There are proposals to remove the virulent genes from viruses to create vaccines. Plants have been engineered for scientific research, to create new colors in plants, deliver vaccines and to create enhanced crops. Genetically modified crops are publicly the most controversial GMOs. The majority are engineered for herbicide tolerance or insect resistance. Golden rice has been engineered with three genes that increase its nutritional value. Other prospects for GM crops are as bioreactors for the production of biopharmaceuticals, biofuels or medicines.

Animals are generally much harder to transform and the vast majority are still at the research stage. Mammals are the best model organisms for humans, making ones genetically engineered to resemble serious human diseases important to the discovery and development of treatments. Human proteins expressed in mammals are more likely to be similar to their natural counterparts than those expressed in plants or microorganisms. Livestock are modified with the intention of improving economically important traits such as growth-rate, quality of meat, milk composition, disease resistance and survival. Genetically modified fish are used for scientific research, as pets and as a food source. Genetic engineering has been proposed as a way to control mosquitos, a vector for many deadly diseases. Although human gene therapy is still relatively new, it has been used to treat genetic disorders such as severe combined immunodeficiency, and Leber's congenital amaurosis.

Many objections have been raised over the development of GMO's, particularly their commercialization. Many of these involve GM crops and whether food produced from them is safe and what impact growing them will have on the environment. Other concerns are the objectivity and rigor of regulatory authorities, contamination of non-genetically modified food, control of the food supply, patenting of life and the use of intellectual property rights. Although there is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, GM food safety is a leading issue with critics. Gene flow, impact on non-target organisms and escape are the major environmental concerns. Countries have adopted regulatory measures to deal with these concerns. There are differences in the regulation for the release of GMOs between countries, with some of the most marked differences occurring between the US and Europe. Key issues concerning regulators include whether GM food should be labeled and the status of gene edited organisms.

, the first genetically modified animal to be sold as a pet]] A genetically modified organism (GMO) is an organism whose genetic material has been altered using genetic engineering techniques. Organisms that have been genetically modified include micro-organisms such as bacteria and yeast, insects, plants, fish, and mammals. GMOs are the source of genetically modified foods, and are also widely used in scientific research and to produce goods other than food. The term GMO is very close to the technical legal term, 'living modified organism' defined in the Cartagena Protocol on Biosafety, which regulates international trade in living GMOs (specifically, “any living organism that possesses a novel combination of genetic material obtained through the use of modern biotechnology”).

This article focuses on what organisms have been genetically engineered, and for what purposes. The article on genetic engineering focuses on the history and methods of genetic engineering, and on applications of genetic engineering and of GMOs. Both articles cover much of the same ground but with different organizations (sorted by organism in this article; sorted by application in the other). There are separate articles on genetically modified crops, genetically modified food, regulation of the release of genetic modified organisms, and controversies.

Production

Genetic modification involves the mutation, insertion, or deletion of genes. When genes are inserted, they usually come from a different species, which is a form of horizontal gene transfer. In nature this can occur when exogenous DNA penetrates the cell membrane for any reason. To do this artificially may require attaching the genes to a virus or just physically inserting the extra DNA into the nucleus of the intended host with a very small syringe, with the use of electroporation using electricity to permeate the cell membrane for transfection or with very small particles fired from a gene gun.<ref>Cornell Chronicle, May 14, 1987, page 3.Biologists invent gun for shooting cells with DNA</ref><ref>Sanford JC et al (1987) Delivery of substances into cells and tissues using a particle bombardment process. Journal of Particulate Science and Technology 5:27-37.</ref><ref>Klein, TM et al (1987) High-velocity microprojectiles for delivering nucleic acids into living cells. Nature 327:70-73.</ref> However, other methods exploit natural forms of gene transfer, such as the ability of Agrobacterium to transfer genetic material to plants,<ref>

</ref> or the ability of lentiviruses to transfer genes to animal cells.<ref>

</ref>

History

The general principle of producing a GMO is to alter the genetic material of an organism's genome. This may involve mutating, deleting, or adding genetic material. When genetic material from a different species is added, the resulting DNA is called recombinant DNA and the organism is called a transgenic organism. The first recombinant DNA molecules were produced by Paul Berg in 1972.<ref>

</ref><ref name=“Sateesh2008”>

</ref>

Uses

GMOs are used in biological and medical research, production of pharmaceutical drugs, experimental medicine (e.g. gene therapy), and agriculture (e.g. golden rice, resistance to herbicides). The term “genetically modified organism” does not always imply, but can include, targeted insertions of genes from one species into another. For example, a gene from a jellyfish, encoding a fluorescent protein called GFP, can be physically linked and thus co-expressed with mammalian genes to identify the location of the protein encoded by the GFP-tagged gene in the mammalian cell. Such methods are useful tools for biologists in many areas of research, including those who study the mechanisms of human and other diseases or fundamental biological processes in eukaryotic or prokaryotic cells.

Plants

Transgenic plants

corn]] Transgenic plants have been engineered for scientific research, to create new colours in plants, and to create different crops.

In research, plants are engineered to help discover the functions of certain genes. One way to do this is to knock out the gene of interest and see what phenotype develops. Another strategy is to attach the gene to a strong promoter and see what happens when it is over expressed. A common technique used to find out where the gene is expressed is to attach it to GUS or a similar reporter gene that allows visualisation of the location.<ref>

</ref>'

After thirteen years of collaborative research, an Australian company – Florigene, and a Japanese company – Suntory, created a blue rose (actually lavender or mauve) in 2004.<ref>Nosowitz, Dan (15 September 2011) Suntory Creates Mythical Blue (Or, Um, Lavender-ish) Rose Popular Science, Retrieved 30 August 2012</ref> The genetic engineering involved three alterations – adding two genes, and interfering with another. One of the added genes was for the blue plant pigment delphinidin cloned from the pansy.<ref name=physorg>Phys.Org website. April 4, 2005 Plant gene replacement results in the world's only blue rose</ref> The researchers then used RNA interference (RNAi) technology to depress all color production by endogenous genes by blocking a crucial protein in color production, called dihydroflavonol 4-reductase) (DFR), and adding a variant of that protein that would not be blocked by the RNAi but that would allow the delphinidin to work.<ref name=physorg/> The roses are sold worldwide.<ref>Kyodo (11 September 2011 Suntory to sell blue roses overseas The Japan Times, Retrieved 30 August 2012</ref><ref>Wired Report 2011</ref> Florigene has also created and sells lavender-colored carnations that are genetically engineered in a similar way.<ref name=physorg />

Simple plants and plant cells have been genetically engineered for production of biopharmaceuticals in bioreactors as opposed to cultivating plants in open fields. Work has been done with duckweed Lemna minor,<ref>Gasdaska JR et al (2003) Advantages of Therapeutic Protein Production in the Aquatic Plant Lemna. BioProcessing Journal Mar/Apr 2003 pp 49–56 ://www.bioprocessingjournal.com/bioprocessingjournal.com/index.php/article-downloads/329-j22-advantages-of-therapeutic-protein-production-in-the-aquatic-plant-lemna</ref> the algae Chlamydomonas reinhardtii<ref>(10 December 2012) Engineering algae to make complex anti-cancer 'designer' drug PhysOrg, Retrieved 15 April 2013</ref> and the moss Physcomitrella patens.<ref>Büttner-Mainik, A., et al (2011): Production of biologically active recombinant human factor H in Physcomitrella. Plant Biotechnology Journal 9, 373–383. ://onlinelibrary.wiley.com/doi/10.1111/j.1467-7652.2010.00552.x/abstract</ref><ref>Baur, A., R. Reski, G. Gorr (2005): Enhanced recovery of a secreted recombinant human growth factor using stabilizing additives and by co-expression of human serum albumin in the moss Physcomitrella patens. Plant Biotech. J. 3, 331–340 ://www.ncbi.nlm.nih.gov/pubmed/17129315</ref> An Israeli company, Protalix, has developed a method to produce therapeutics in cultured transgenic carrot and tobacco cells.<ref>Protalix website – technology platform</ref> Protalix and its partner, Pfizer, received FDA approval to market its drug Elelyso, a treatment for Gaucher's Disease, in 2012.<ref>Gali Weinreb and Koby Yeshayahou for Globes May 2, 2012. FDA approves Protalix Gaucher treatment</ref>

GM crops

In agriculture, currently marketed genetically engineered crops have traits such as resistance to pests, resistance to herbicides, increased nutritional value, or production of valuable goods such as drugs (pharming); products under development include crops able to thrive in environmental conditions outside the species' native range or in changed conditions in their range (e.g. drought or salt resistance); products that existed and have been withdrawn include those with extended product shelf life such as the Flavr-savr tomato. Since the first commercial cultivation of genetically modified plants in 1996, they have been modified to be tolerant to the herbicides glufosinate and glyphosate, to be resistant to virus damage as in Ringspot virus-resistant GM papaya, grown in Hawaii, and to produce the Bt toxin, an insecticide that is documented as non-toxic to mammals.<ref>EPA Reregistration Eligibility Decision (RED) Bacillus thuringiensis “The potential risk to humans from dietary, non-dietary and occupational exposures of the delta-endotoxins and most of the cellular components of Bacillus thuringiensis are considered negligible.” (p 34) “As described in the environmental assessment, section III(C), there should be no unreasonable adverse effects on nontarget organisms, or ground or surface water contamination concerns, from the delta-endotoxins and most of the cellular components of Bacillus thuringiensis when used according to currently approved label rates.” (p 34</ref><ref>http://www.agf.gov.bc.ca/pesticides/infosheets/bt.pdf. Retrieved 21 January 2011</ref>

Plants, including algae, jatropha, maize, poplars<ref>Hope, Alan (3 April 2013), News in brief: The Bio Safety Council&nbsp;...", Flanders Today, Page 2; In 2013, the Flemish Institute for Biotechnology was supervising a trial of 448 poplar trees genetically engineered to produce less lignin so that they would be more suitable for conversion into bio-fuels.</ref> and other plants have been genetically modified for use in producing fuel, known as biofuel.

Second and third generation GM crops are on the market and under development with improved nutrition profiles and increased yields or ability to thrive in difficult environments.<ref>http://dtma.cimmyt.org. Retrieved 21 January 2011</ref> GM oilseed crops on the market today offer improved oil profiles for processing or healthier edible oils.<ref>Canadian Food Inspection Agency. DD2009-76: Determination of the Safety of Pioneer Hi-Bred Production Ltd.'s Soybean (Glycine max (L.) Merr.) Event 305423 Issued: 2009-04 ://www.inspection.gc.ca/english/plaveg/bio/dd/dd0976e.shtml. Retrieved January 2011</ref> Other examples include: a genetically modified cassava with lower cyanogen glucosides and enhanced with protein and other nutrients;<ref>

</ref> golden rice, developed by the International Rice Research Institute (IRRI), has been discussed as a possible cure for Vitamin A deficiency;<ref>About Golden Rice International Rice Research Institute. Retrieved 20 August 2012</ref> a vitamin-enriched corn derived from South African white corn variety;<ref>Shaista Naqvi, et al. ''Transgenic multivitamin corn through biofortification of endosperm with three vitamins representing three distinct metabolic pathways'' PNAS April 27, 2009.</ref> camelina sativa that accumulates high levels of oils similar to fish oils.<ref>Crop plants – "green factories" for fish oils, Rothamsted Research 14-11-2013.</ref><ref> Successful high-level accumulation of fish oil omega-3 long chain polyunsaturated fatty acids in a transgenic oilseed crop, Ruiz-Lopez, Noemi et al., The Plant Journal, accepted article, DOI:10.1111/tpj.12378, 2013.</ref>

See the Controversies section below, and genetically modified food controversies article for discussions of issues about GM crops and GM food.

Cisgenic plants

Cisgenesis, sometimes also called intragenesis, is a product designation for a category of genetically engineered plants. A variety of classification schemes have been proposed<ref>

</ref> that order genetically modified organisms based on the nature of introduced genotypical changes rather than the process of genetic engineering.

While some genetically modified plants are developed by the introduction of a gene originating from distant, sexually incompatible species into the host genome, cisgenic plants contain genes that have been isolated either directly from the host species or from sexually compatible species. The new genes are introduced using recombinant DNA methods and gene transfer. Some scientists hope that the approval process of cisgenic plants might be simpler than that of proper transgenics,<ref>

</ref> but it remains to be seen.<ref>Prins, T.W. and Kok, E.J. (2010) Food and feed safety aspects of cisgenic crop plant varieties Report 2010.001, Project number: 120.72.667.01, RIKILT – Institute of Food Safety, Netherlands. Retrieved 6 September 2010.</ref>

Microbes

Bacteria were the first organisms to be modified in the laboratory, due to their simple genetics.<ref name=Melo>

</ref> These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine.<ref name=Leader2008>

<br />Leader 2008 — Fee required for access to full text.</ref>

Genetically modified bacteria are used to produce the protein insulin to treat diabetes.<ref name=Walsh2005>

<br />Walsh 2005 — Fee required for access to full text.</ref> Similar bacteria have been used to produce biofuels,<ref>Summers, Rebecca (24 April 2013) Bacteria churn out first ever petrol-like biofuel New Scientist, Retrieved 27 April 2013</ref> clotting factors to treat haemophilia,<ref name=Pipe2008>

</ref> and human growth hormone to treat various forms of dwarfism.<ref name=Bryant2007>

<br />Bryant 2007 — Fee required for access to full text.</ref><ref>

</ref>

In addition, various genetically engineered micro-organisms are routinely used as sources of enzymes for the manufacture of a variety of processed foods. These include alpha-amylase from bacteria, which converts starch to simple sugars, chymosin from bacteria or fungi that clots milk protein for cheese making, and pectinesterase from fungi which improves fruit juice clarity.<ref>Panesar, Pamit et al (2010) “Enzymes in Food Processing: Fundamentals and Potential Applications”, Chapter 10, I K International Publishing House, ISBN 978-93-80026-33-6</ref>

Mammals

, like the blotched mouse shown, are created through genetic modification techniques like gene targeting.]]

Genetically modified mammals are an important category of genetically modified organisms.<ref name=“EFSA”>EFSA (2012). Genetically modified animals. Europe: EFSA.http://www.efsa.europa.eu/en/topics/topic/gmanimals.htm.</ref> Ralph L. Brinster and Richard Palmiter developed the techniques responsible for transgenic mice, rats, rabbits, sheep, and pigs in the early 1980s, and established many of the first transgenic models of human disease, including the first carcinoma caused by a transgene. The process of genetically engineering animals is a slow, tedious, and expensive process. However, new technologies are making genetic modifications easier and more precise.<ref name=Murray2010>Murray, Joo (20). Genetically modified animals. Canada: Brainwaving.http://www.brainwaving.com/2010/07/28/genetically-modified-animals/.</ref>

The first transgenic (genetically modified) animal was produced by injecting DNA into mouse embryos then implanting the embryos in female mice.<ref>

</ref>

Genetically modified animals currently being developed can be placed into six different broad classes based on the intended purpose of the genetic modification:

  1. to research human diseases (for example, to develop animal models for these diseases);
  2. to produce industrial or consumer products (fibres for multiple uses);
  3. to produce products intended for human therapeutic use (pharmaceutical products or tissue for implantation);
  4. to enrich or enhance the animals' interactions with humans (hypo-allergenic pets);
  5. to enhance production or food quality traits (faster growing fish, pigs that digest food more efficiently);
  6. to improve animal health (disease resistance)<ref name=“rudenko”>rudinko, larisa (20). Guidance for industry. USA: Center for veterinary medicine Link.</ref>

Research use

Transgenic animals are used as experimental models to perform phenotypic and for testing in biomedical research.<ref name=“pmid10434294”>

</ref>

Genetically modified (genetically engineered) animals are becoming more vital to the discovery and development of cures and treatments for many serious diseases. By altering the DNA or transferring DNA to an animal, we can develop certain proteins that may be used in medical treatment. Stable expressions of human proteins have been developed in many animals, including sheep, pigs, and rats. Human-alpha-1-antitrypsin,<ref>

</ref> which has been tested in sheep and is used in treating humans with this deficiency and transgenic pigs with human-histo-compatibility have been studied in the hopes that the organs will be suitable for transplant with less chances of rejection.

Scientists have genetically engineered several organisms, including some mammals, to include green fluorescent protein (GFP) for medical research purposes (Chalfie, Shimoura, and Tsien were awarded the Nobel prize in 2008 for GFP<ref>

</ref>). For example fluorescent pigs have been bred in the US in 2000,<ref>

</ref> in Korea in 2002,<ref>

</ref> in Taiwan in 2006,<ref name=Hogg2005>Hogg, Chris (12 January 2006) Taiwan Breeds Green-Glowing Pigs BBC, Retrieved 31 August 2012</ref> in China in 2008<ref name = China>Staff (8 January 2008) Fluorescent Chinese pig passes on trait to offspring AFP, Retrieved 31 August 2012</ref> and Japan in 2009.<ref name = Japan>

</ref> These pigs were bred to study human organ transplants,<ref name = China/> regenerating ocular photoreceptor cells,<ref name = Randall>Randall S. et al (2008) Genetically Modified Pigs for Medicine and Agriculture Biotechnology and Genetic Engineering Reviews – Vol. 25, 245–266, Retrieved 31 August 2012</ref> neuronal cells in the brain,<ref name = Randall/> regenerative medicine via stem cells,<ref>Staff (2006) NTU produces green fluorescent pigs for medical research Taiwan Central News Agency, Retrieved 31 August 2012</ref> tissue engineering,<ref name = Japan/> and other diseases. In 2011 a Japanese-American Team created green-fluorescent cats in order to find therapies for HIV/AIDS and other diseases<ref name=Wongsrikeao_2011>

</ref> as Feline immunodeficiency virus (FIV) is related to HIV.<ref>Staff (3 April 2012) Biology of HIV National Institute of Allergy and Infectious Diseases, Retrieved 31 August 2012.</ref>

In 2009, scientists in Japan announced that they had successfully transferred a gene into a primate species (marmosets) and produced a stable line of breeding transgenic primates for the first time.<ref>

</ref><ref>

</ref> Their first research target for these marmosets was Parkinson's disease, but they were also considering Amyotrophic lateral sclerosis and Huntington's disease.<ref>

</ref>

Producing human therapeutics

Within the field known as pharming, intensive research has been conducted to develop transgenic animals that produce biotherapeutics.<ref>Louis-Marie Houdebine (2009) Production of Pharmaceutical by transgenic animals. Comparative Immunology, Microbiology & Infectious Diseases 32(2): 107–121 ://www.idpublications.com/journals/pdfs/cimid/cimid_mostdown_1.pdf</ref> On 6 February 2009, the U.S. Food and Drug Administration approved the first human biological drug produced from such an animal, a goat. The drug, ATryn, is an anticoagulant which reduces the probability of blood clots during surgery or childbirth. It is extracted from the goat's milk.<ref>Britt Erickson, 10 February 2009, for Chemical & Engineering News. FDA Approves Drug From Transgenic Goat Milk Accessed October 6, 2012</ref>

Production or food quality traits

Enviropig was a genetically enhanced line of Yorkshire pigs in Canada created with the capability of digesting plant phosphorus more efficiently than conventional Yorkshire pigs. The project ended in 2012.<ref name=“Guelph”>Guelph(2010). Enviropig. Canada: http://www.uoguelph.ca/enviropig/index.shtml/.</ref><ref>Schimdt, Sarah. Genetically engineered pigs killed after funding ends, Postmedia News, June 22, 2012. Accessed July 31, 2012.</ref> These pigs produced the enzyme phytase, which breaks down the indigestible phosphorus, in their saliva. The enzyme was introduced into the pig chromosome by pronuclear microinjection. With this enzyme, the animal is able to digest cereal grain phosphorus.<ref name=“Guelph”/><ref name=“Canada”>

</ref> The use of these pigs would reduce the potential of water pollution since they excrete from 30 to 70.7% less phosphorus in manure depending upon the age and diet.<ref name=“Guelph”/><ref name=“Canada”/> The lower concentrations of phosphorus in surface runoff reduces algal growth, because phosphorus is the limiting nutrient for algae.<ref name=“Guelph”/> Because algae consume large amounts of oxygen, it can result in dead zones for fish.

In 2011, Chinese scientists generated dairy cows genetically engineered with genes for human beings to produce milk that would be the same as human breast milk.<ref name=“stevenson”>stevenson, heidi(2011). Scientists Use Human Genes in Animals, So Cows Produce Human-Like Milk—Or Do They? USA:http://www.gaia-health.com/articles401/000433-human-genes-cows-produce-human-milk.shtml/.</ref> This could potentially benefit mothers who cannot produce breast milk but want their children to have breast milk rather than formula. Aside from milk production, the researchers claim these transgenic cows to be identical to regular cows.<ref>

</ref> Two months later scientists from Argentina presented Rosita, a transgenic cow incorporating two human genes, to produce milk with similar properties as human breast milk.<ref>

</ref> In 2012, researchers from New Zealand also developed a genetically engineered cow that produced allergy-free milk.<ref>

</ref>

In 2006, a pig was engineered to produce omega-3 fatty acids through the expression of a roundworm gene.<ref>

</ref>

Goats have been genetically engineered to produce milk with strong spiderweb-like silk proteins in their milk.<ref>Zyga, Lisa(2010). Scientist bred goats that produce spider silk. Link.</ref>

Genetically modified fish have been developed with promoters driving an over-production of growth hormone for use in the aquaculture industry to increase the speed of development and potentially reduce fishing pressure on wild stocks. AquaBounty, a biotechnology company working on bringing a GM salmon to market, claims that their GM AquAdvantage salmon can mature in half the time it takes non-GM salmon and achieves twice the size.<ref name=AquaAdvantage>{AquAdvantage salmon}://www.aquabounty.com/products/aquadvantage-295.aspx</ref> AquaBounty has applied for regulatory approval to market their GM salmon in the US. As of May 2012 the application was still pending.<ref name=NYTImes2012>Andrew Pollack for the New York Times. "An Entrepreneur Bankrolls a Genetically Engineered Salmon" Published: May 21, 2012. Accessed October 7, 2012</ref>On 25 November 2013 Canada approved commercial scale production and export of GM Salmon eggs but they are not approved for human consumption in Canada.<ref>

</ref>

Human gene therapy

Gene therapy,<ref>

</ref> uses genetically modified viruses to deliver genes that can cure disease in humans. Although gene therapy is still relatively new, it has had some successes. It has been used to treat genetic disorders such as severe combined immunodeficiency,<ref>

</ref> and Leber's congenital amaurosis.<ref>Richards, Sabrina (6 November 2012) Gene Therapy Arrives in Europe The Scientist, Retrieved 15 April 2013</ref> Treatments are also being developed for a range of other currently incurable diseases, such as cystic fibrosis,<ref>

</ref> sickle cell anemia,<ref>

</ref> Parkinson's disease,<ref>

</ref><ref>Gallaher, James Gene therapy 'treats' Parkinson's disease BBC News Health, 17 March 2011. Retrieved 24 April 2011</ref> cancer,<ref>Urbina, Zachary (12 February 2013) Genetically Engineered Virus Fights Liver Cancer United Academics, Retrieved 15 February 2013</ref><ref>

</ref><ref>Coghlan, Andy (26 March 2013) Gene therapy cures leukaemia in eight days The New Scientist, Retrieved 15 April 2013</ref> diabetes,<ref>Staff (13 February 2013) Gene therapy cures diabetic dogs New Scientist, Retrieved 15 February 2013</ref> heart disease<ref>(30 April 2013) New gene therapy trial gives hope to people with heart failure British Heart Foundation, Retrieved 5 may 2013</ref> and muscular dystrophy.<ref>

</ref> Current gene therapy technology only targets the non-reproductive cells meaning that any changes introduced by the treatment can not be transmitted to the next generation. Gene therapy targeting the reproductive cells—so-called “Germ line Gene Therapy”—is very controversial and is unlikely to be developed in the near future.

Insects

Fruit flies

In biological research, transgenic fruit flies (Drosophila melanogaster) are model organisms used to study the effects of genetic changes on development.<ref>First Transgenic Mice and Fruit Flies</ref> Fruit flies are often preferred over other animals due to their short life cycle, low maintenance requirements, and relatively simple genome compared to many vertebrates.

Mosquitoes

In 2010, scientists created “malaria-resistant mosquitoes” in the laboratory.<ref>Gallagher, James GM mosquitoes offer malaria hope BBC News, Health, 20 April 2011. Retrieved 22 April 2011</ref><ref>

</ref><ref>

</ref> The World Health Organization estimated that Malaria killed almost one million people in 2008.<ref>World Health Organization, Malaria, Key Facts Retrieved 22 April 2011</ref> Genetically modified male mosquitoes containing a lethal gene have been developed in order to combat the spread of Dengue fever.<ref>

</ref> Aedes aegypti mosquitoes, the single most important carrier of dengue fever, were reduced by 80% in a 2010 trial of these GM mosquitoes in the Cayman Islands.<ref>

</ref><ref>Staff (March 2011) Cayman demonstrates RIDL potential Oxitec Newsletter, March 2011. Retrieved 20 September 2011</ref> Between 50 and 100 million people are affected by Dengue fever every year and 40,000 people die from it.<ref name = NS20110914>Nicholls, Henry (14 September 2011) Swarm troopers: Mutant armies waging war in the wild The New Scientist. Retrieved 20 September 2011</ref>

Bollworms

A strain of Pectinophora gossypiella (Pink bollworm) has been developed that contains a fluorescent marker in their DNA. This allows researchers to monitor bollworms that have been sterilized by radiation and released in order to reduce bollworm infestation.<ref name = NS20110914/><ref>Staff ''Pectinophora gossypiella'' (pink bollworm) OX1138 Oxitec. Retrieved 30 September 2011</ref>

Aquatic life

Cnidarians

Cnidarians such as Hydra and the sea anemone Nematostella vectensis have become attractive model organisms to study the evolution of immunity and certain developmental processes. An important technical breakthrough was the development of procedures for generation of stably transgenic hydras and sea anemones by embryo microinjection.<ref>

</ref>

Fish

GM fish are used for scientific research and as pets, and are being considered for use as food and as aquatic pollution sensors.

Genetically engineered fish are widely used in basic research in genetics and development. Two species of fish, zebrafish and medaka, are most commonly modified because they have optically clear chorions (shells), rapidly develop, and the 1-cell embryo is easy to see and microinject with transgenic DNA.<ref>Hackett, P.B., Ekker, S.E. and Essner, J.J. (2004) Applications of transposable elements in fish for transgenesis and functional genomics. Fish Development and Genetics (Z. Gong and V. Korzh, eds.) World Scientific, Inc., Chapter 16, 532–580.</ref>

The GloFish is a patented<ref>Published PCT Application WO2000049150 “Chimeric Gene Constructs for Generation of Fluorescent Transgenic Ornamental Fish.” National University of Singapore ://patentscope.wipo.int/search/en/detail.jsf?docId=WO2000049150</ref> brand of genetically modified (GM) fluorescent zebrafish with bright red, green, and orange fluorescent color. Although not originally developed for the ornamental fish trade, it became the first genetically modified animal to become publicly available as a pet when it was introduced for sale in 2003.<ref>Eric Hallerman Glofish, The First GM Animal Commercialized: Profits amid Controversy. June, 2004. Accessed September 3, 2012.://www.isb.vt.edu/articles/jun0405.htm</ref> They were quickly banned for sale in California.<ref>Schuchat S. (2003) Why GloFish won't glow in California. San Francisco Chronicle.://sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/12/17/EDGQV3KOLB1.DTL</ref>

Genetically modified fish have been developed with promoters driving an over-production of “all fish” growth hormone for use in the aquaculture industry to increase the speed of development and potentially reduce fishing pressure on wild stocks. This has resulted in dramatic growth enhancement in several species, including salmon,<ref name=“nature salmon”>Shao Jun Du et al. (1992) Growth Enhancement in Transgenic Atlantic Salmon by the Use of an “All Fish” Chimeric Growth Hormone Gene Construct. Nature Biotechnology 10, 176–181 ://www.nature.com/nbt/journal/v10/n2/abs/nbt0292-176.html</ref> trout<ref name=“nature trout”>Devlin RF et al (2001) Growth of domesticated transgenic fish. Nature 409, 781–782 ://www.nature.com/nature/journal/v409/n6822/full/409781a0.html</ref> and tilapia.<ref name=tilapia>Rahman MA et al. (2001) Growth and nutritional trials on transgenic Nile tilapia containing an exogenous fish growth hormone gene. Journal of Fish Biology 59(1):62–78 ://onlinelibrary.wiley.com/doi/10.1111/j.1095-8649.2001.tb02338.x/abstract</ref> AquaBounty, a biotechnology company working on bringing a GM salmon to market, claims that their GM AquAdvantage salmon can mature in half the time it takes non-GM salmon and achieves twice the size.<ref name=“AquaAdvantage”/> AquaBounty has applied for regulatory approval to market their GM salmon in the US. As of December 2012 the application was still pending.<ref name=NYTImes2012 /><ref name = FDA>Staff (26 December 2012) Draft Environmental Assessment and Preliminary Finding of No Significant Impact Concerning a Genetically Engineered Atlantic Salmon; Availability Federal Register / Vol. 77, No. 247 / Wednesday, December 26, 2012 / Notices, Retrieved 2 January 2013</ref>

Several academic groups have been developing GM zebrafish to detect aquatic pollution. The lab that originated the GloFish discussed above originally developed them to change color in the presence of pollutants, to be used as environmental sensors.<ref>National University of Singapore Enterprise webpage</ref><ref>Zebra Fish as Pollution Indicators Page last modified on 31 July 2001. Accessed October 2012</ref> A lab at University of Cincinnati has been developing GM zebrafish for the same purpose,<ref>Carvan MJ et al (2000) Transgenic zebrafish as sentinels for aquatic pollution. Ann N Y Acad Sci. 2000;919:133–47 ://www.ncbi.nlm.nih.gov/pubmed/11083105</ref><ref>Nebert DW et al (2002) Use of Reporter Genes and Vertebrate DNA Motifs in Transgenic Zebrafish as Sentinels for Assessing Aquatic Pollution. Environmental Health Perspectives 110(1):A15 | January 2002 ://www.ncbi.nlm.nih.gov/pmc/articles/PMC1240712/pdf/ehp0110-a0012d.pdf</ref> as has a lab at Tulane University.<ref>Mattingly CJ et al (2001) Green fluorescent protein (GFP) as a marker of aryl hydrocarbon receptor (AhR) function in developing zebrafish (Danio rerio). Environ Health Perspect. 2001 Aug;109(8):845–9 ://www.ncbi.nlm.nih.gov/pubmed/11564622</ref>

Regulation

The regulation of genetic engineering concerns the approaches taken by governments to assess and manage the risks associated with the use of genetic engineering technology and the development and release of genetically modified organisms (GMO), including genetically modified crops and genetically modified fish. There are differences in the regulation of GMOs between countries, with some of the most marked differences occurring between the USA and Europe.<ref>

</ref> Regulation varies in a given country depending on the intended use of the products of the genetic engineering. For example, a crop not intended for food use is generally not reviewed by authorities responsible for food safety.<ref name=PotatoPro>PotatoPro</ref> The European Union differentiates between approval for cultivation within the EU and approval for import and processing. While only a few GMOs have been approved for cultivation in the EU a number of GMOs have been approved for import and processing.<ref name=“Wesseler-2011”>Wesseler, J. and N. Kalaitzandonakes (2011): Present and Future EU GMO policy. In Arie Oskam, Gerrit Meesters and Huib Silvis (eds.), EU Policy for Agriculture, Food and Rural Areas. Second Edition, pp.&nbsp;23–323 – 23-332. Wageningen: Wageningen Academic Publishers</ref> The cultivation of GMOs has triggered a debate about coexistence of GM and nonGM crops. Depending on the coexistence regulations incentives for cultivation of GM crops differ.<ref name=“Beckman-2011”>Beckmann, V., C. Soregaroli, J. Wesseler (2011): Coexistence of genetically modified (GM) and non-modified (non GM) crops: Are the two main property rights regimes equivalent with respect to the coexistence value? In “Genetically modified food and global welfare” edited by Colin Carter, GianCarlo Moschini and Ian Sheldon, pp&nbsp;201–224. Volume 10 in Frontiers of Economics and Globalization Series. Bingley, UK: Emerald Group Publishing</ref>

Controversy

There is controversy over GMOs, especially with regard to their use in producing food. The dispute involves consumers, biotechnology companies, governmental regulators, non-governmental organizations, and scientists. The key areas of controversy related to GMO food are whether GM food should be labeled, the role of government regulators, the effect of GM crops on health and the environment, the effect on pesticide resistance, the impact of GM crops for farmers, and the role of GM crops in feeding the world population.

There is broad scientific consensus that food on the market derived from GM crops poses no greater risk than conventional food.<ref name=“AAAS”>American Association for the Advancement of Science (AAAS), Board of Directors (2012). Legally Mandating GM Food Labels Could Mislead and Falsely Alarm Consumers</ref><ref name=“decade_of_EU-funded_GMO_research”>

</ref><ref name=“Ronald”>

</ref> No reports of ill effects have been documented in the human population from ingesting GM food.<ref name=“AMA”>American Medical Association (2012). Report 2 of the Council on Science and Public Health: Labeling of Bioengineered Foods “Bioengineered foods have been consumed for close to 20 years, and during that time, no overt consequences on human health have been reported and/or substantiated in the peer-reviewed literature.” (first page)</ref><ref name=NRC2004>United States Institute of Medicine and National Research Council (2004). Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects. National Academies Press. Free full-text. National Academies Press. pp R9-10: “In contrast to adverse health effects that have been associated with some traditional food production methods, similar serious health effects have not been identified as a result of genetic engineering techniques used in food production. This may be because developers of bioengineered organisms perform extensive compositional analyses to determine that each phenotype is desirable and to ensure that unintended changes have not occurred in key components of food.”</ref><ref name=“Key”>

</ref> Although labeling of GMO products in the marketplace is required in many countries, it is not required in the United States and no distinction between marketed GMO and non-GMO foods is recognized by the US FDA.

Advocacy groups such as Greenpeace, The Non-GMO Project and Organic Consumers Association say that risks of GM food have not been adequately identified and managed, and have questioned the objectivity of regulatory authorities. Opponents say that food derived from GMOs may be unsafe and propose it be banned, or at least labeled. They have expressed concerns about the objectivity of regulators and rigor of the regulatory process, about contamination of the non-GM food supply, about effects of GMOs on the environment and nature, and about the consolidation of control of the food supply in companies that make and sell GMOs.

Recognition of the originators of GM crops

On June 19, 2013 the leaders of the three research teams that first applied genetic engineering to crops, Robert T. Fraley of Monsanto; Marc Van Montagu of Ghent University in Belgium and founder of Plant Genetic Systems and Crop Design; and Mary-Dell Chilton of the University of Washington and Washington University in St. Louis and Syngenta, were awarded with the World Food Prize. The prize, of $250,000, is awarded to people who improve the “quality, quantity or availability” of food in the world. The three competing teams first presented their results in January 1983.<ref name=NYT61913>

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See also

References

genetically_modified_organism.txt · Last modified: 2020/03/12 18:34 (external edit)