A genetically modified organism (GMO) or genetically engineered organism (GEO) is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one molecule to create a new set of genes. This DNA is then transferred into an organism, giving it modified or novel genes. Transgenic organisms, a subset of GMOs, are organisms which have inserted DNA that originated in a different species.
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Genetic modification involves the 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, or with very small particles fired from a gene gun.[1] However, other methods exploit natural forms of gene transfer, such as the ability of Agrobacterium to transfer genetic material to plants,[2] or the ability of lentiviruses to transfer genes to animal cells.[3]
The general principle of producing a GMO is to add new genetic material into an organism's genome. This is called genetic engineering and was made possible through the discovery of DNA and the creation of the first recombinant bacteria in 1973; an existing bacterium E. coli expressing an exogenic Salmonella gene.[4] This led to concerns in the scientific community about potential risks from genetic engineering, which were thoroughly discussed at the Asilomar Conference. One of the main recommendations from this meeting was that government oversight of recombinant DNA research should be established until the technology was deemed safe.[5][6] Herbert Boyer then founded the first company to use recombinant DNA technology, Genentech, and in 1978 the company announced creation of an E. coli strain producing the human protein insulin.[7]
In 1986, field tests of bacteria genetically engineered to protect plants from frost damage (ice-minus bacteria) at a small biotechnology company called Advanced Genetic Sciences of Oakland, California, were repeatedly delayed by opponents of biotechnology. In the same year, a proposed field test of a microbe genetically engineered for a pest resistance protein by Monsanto Company was dropped.
GMOs are used in biological and medical research, production of pharmaceutical drugs, experimental medicine (e.g. gene therapy), and agriculture (e.g. golden rice). 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.
To date the broadest and most controversial application of GMO technology is patent-protected food crops which are resistant to commercial herbicides or are able to produce pesticidal proteins from within the plant, or stacked trait seeds, which do both. The largest share of the GMO crops planted globally are owned by the US firm Monsanto.[8] In 2007, Monsanto's trait technologies were planted on 246 million acres (1,000,000 km2) throughout the world, a growth of 13 percent from 2006.
In the corn market, Monsanto's triple-stack corn—which combines Roundup Ready 2 weed control technology with YieldGard Corn Borer and YieldGard Rootworm insect control—is the market leader in the United States. U.S. corn farmers planted more than 32 million acres (130,000 km2) of triple-stack corn in 2008,[9] and it is estimated the product could be planted on 56 million acres (230,000 km2) in 2014-2015. In the cotton market, Bollgard II with Roundup Ready Flex was planted on approximately 5 million acres (20,000 km2) of U.S. cotton in 2008.[10]
According to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA), of the approximately 14 million farmers who grew biotech crops in 2009, some 90% were resource-poor farmers in developing countries. These include some 7 million farmers in the cotton-growing areas of China, an estimated 5.6 million small farmers in India (Bt cotton), 250,000 in the Philippines, South Africa (biotech cotton, maize and soybeans often grown by subsistence women farmers) and the other twelve developing countries which grew biotech crops in 2009.[11] 10 million more small and resource-poor farmers may have been secondary beneficiaries of Bt cotton in China.
The global commercial value of biotech crops grown in the 2008 was estimated to be US$130 billion.[11]
In the United States the United States Department of Agriculture (USDA) reports on the total area of GMO varieties planted.[12] According to National Agricultural Statistics Service, the states published in these tables represent 81–86 percent of all corn planted area, 88–90 percent of all soybean planted area, and 81–93 percent of all upland cotton planted area (depending on the year).
USDA does not collect data for global area. Estimates are produced by the International Service for the Acquisition of Agri-biotech Applications (ISAAA) and can be found in the report, "Global Status of Commercialized Transgenic Crops: 2007".[13]
Transgenic animals are also becoming useful commercially. On February 6, 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.[14]
Testing on GMOs in food and feed is routinely done by molecular techniques like DNA microarrays or qPCR. The test can be based on screening elements (like p35S, tNos, pat, or bar) or event-specific markers for the official GMOs (like Mon810, Bt11, or GT73). The array-based method combines multiplex PCR and array technology to screen samples for different potential GMOs,[15] combining different approaches (screening elements, plant-specific markers, and event-specific markers). The qPCR is used to detect specific GMO events by usage of specific primers for screening elements or event-specific markers.
To avoid any kind of false positive or false negative testing outcome, comprehensive controls for every step of the process is mandatory. A CaMV check is important to avoid false positive outcomes based on virus contamination of the sample.
Bacteria were the first organisms to be modified in the laboratory, due to their simple genetics.[16] These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine.[17]
Genetically modified bacteria are used to produce the protein insulin to treat diabetes.[18] Similar bacteria have been used to produce clotting factors to treat haemophilia,[19] and human growth hormone to treat various forms of dwarfism.[20][21]
Transgenic animals are used as experimental models to perform phenotypic and for testing in biomedical research.[22] Other applications include the production of human hormones such as insulin.
In biological research, transgenic fruit flies (Drosophila melanogaster) are model organisms used to study the effects of genetic changes on development.[23] 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.
Genetically modified mammals are an important category of genetically modified organisms. Transgenic mice are often used to study cellular and tissue-specific responses to disease.
In 1999, scientists at the University of Guelph in Ontario, Canada created the genetically engineered Enviropig™. The Enviropig excretes from 30 to 70.7% less phosphorus in manure depending upon the age and diet.[24] In February 2010, Environment Canada determined that Enviropigs are in compliance with the Canadian Environmental Protection Act and can be produced outside of the research context in controlled facilities where they are segregated from other animals.[25]
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.
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.[26]
Genetically modified fish have promoters driving an over-production of "all fish" growth hormone. This resulted in dramatic growth enhancement in several species, including salmonids,[27] carps[28] and tilapias.[29]
Gene therapy,[30] uses genetically modified viruses to deliver genes that can cure disease into human cells. 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,[31] and treatments are being developed for a range of other currently incurable diseases, such as cystic fibrosis,[32] sickle cell anemia,[33] and muscular dystrophy.[34] 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.
Transgenic plants have been engineered to possess several desirable traits, including resistance to pests, herbicides, or harsh environmental conditions; improved product shelf life, and increased nutritional value. 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, a potent insecticide. Most of transgenic varieties grown today are known as first generation transgenics, because the transgenic trait provides benefits to farmers. Plants of the second generation should directly benefit the consumer with nutritional enhancement, taste, texture, etc. Transgenic plants of the second generation are being developed by both public research institutions and private companies. Currently there is no such transgenic variety on the market. Genetically modified sweet potatoes have been enhanced with protein and other nutrients, while golden rice, developed by the International Rice Research Institute, has been discussed as a possible cure for Vitamin A deficiency. In January 2008, scientists altered a carrot so that it would produce calcium and become a possible cure for osteoporosis; however, people would need to eat 1.5 kilograms of carrots per day to reach the required amount of calcium.[32]
The coexistence of GM plants with conventional and organic crops has raised significant concern in many European countries. Since there is separate legislation for GM crops and a high demand from consumers for the freedom of choice between GM and non-GM foods, measures are required to separate foods and feed produced from GMO plants from conventional and organic foods. European research programs such as Co-Extra, Transcontainer, and SIGMEA are investigating appropriate tools and rules. At the field level, biological containment methods include isolation distances and pollen barriers.
Cisgenesis, sometimes also called Intragenesis, is a product designation for a category of genetically engineered plants. A variety of classification schemes have been proposed [35], 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 which 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, but it remains to be seen.
The use of genetically modified organisms has sparked significant controversy in many areas.[36] Some groups or individuals see the generation and use of GMO as intolerable meddling with biological states or processes that have naturally evolved over long periods of time, while others are concerned about the limitations of modern science to fully comprehend all of the potential negative ramifications of genetic manipulation.
The safety of GMOs in the foodchain has been questioned by some environmental groups, with concerns such as the possibilities that GMOs could introduce new allergens into foods, or contribute to the spread of antibiotic resistance.[37] Although all studies published to date have shown no adverse health effects resulting from humans eating genetically modified foods,[38] environmental groups still discourage consumption in many countries, claiming that GM foods are unnatural and therefore unsafe.[39] Such concerns have led to the adoption of laws and regulations that require safety testing of any new organism produced for human consumption.[40]
GMOs' proponents note that because of the safety testing requirements imposed on GM foods, the risk of introducing a plant variety with a new allergene or toxin using genetic modification is much smaller than using traditional breeding processes. An example of an allergenic plant created using traditional breeding is the kiwi.[41] One article calculated that the marketing of GM salmon could reduce the cost of salmon by half, thus increasing salmon consumption and preventing 1,400 deaths from heart attack a year in the United States.[42]
In response to negative public opinion, Monsanto announced its decision to remove their seed cereal business from Europe, and environmentalists crashed a World Trade Organization conference in Cancun that promoted GM foods and was sponsored by Committee for a Constructive Tomorrow (CFACT). Some African nations have refused emergency food aid from developed countries, fearing that the food is unsafe. During a conference in the Ethiopian capital of Addis Ababa, Kingsley Amoako, Executive Secretary of the United Nations Economic Commission for Africa (UNECA), encouraged African nations to accept genetically modified food and expressed dissatisfaction in the public’s negative opinion of biotechnology.[39]
Patrick Mulvany, Chairman of the UK Food Group, accused some governments, especially the Bush administration, of using GM food aid as a way to dispose of unwanted agricultural surpluses. The UN blamed food companies and accused them of violating human rights, calling on governments to regulate these profit-driven firms. It is widely believed that the acceptance of biotechnology and genetically modified foods will also benefit rich research companies and could possibly benefit them more than consumers in underdeveloped nations.[39]
While some groups advocate the complete prohibition of GMOs, others call for mandatory labeling of genetically modified food or other products. Other controversies include the definition of patent and property pertaining to products of genetic engineering. According to the documentary Food, Inc. efforts to introduce labeling of GMOs has repeatedly met resistance from lobbyists and politicians affiliated with companies like Monsanto.
Bruce Stutz's article, “Wanted: GM Seeds for Study,” highlights a story of two dozen scientist who spoke out against the research restrictions put forth by companies producing genetically modified (GM) seeds such as DuPont, Monsanto, and Syngenta. In February 2009, after scientist warned the U.S. Environmental protection Agency (EPA) “that industry influence had made independent analyses of transgenic crops impossible,” the American Seed Trade Association (ASTA) agreed that they “would allow researchers greater freedom to study the effects of GM food crops.” This agreement left many scientist optimistic about the future, but there is little optimism as to whether this agreement has the ability to “alter what has been a research environment rife with obstruction and suspicion.” , [43]
Some groups believe that impoverished nations will not reap the benefits of biotechnology because they do not have easy access to these developments, cannot afford modern agricultural equipment, and certain aspects of the system revolving around intellectual property rights are unfair to "undeveloped countries". For example, The CGIAR (Consultative Group of International Agricultural Research) is an aid and research organization that has been working to achieve sustainable food security and decrease poverty in undeveloped countries since its formation in 1971. In an evaluation of CGIAR, the World Bank praised its efforts but suggested a shift to genetics research and productivity enhancement. This plan has several obstacles such as patents, commercial licenses, and the difficulty that third world countries have in accessing the international collection of genetic resources and other intellectual property rights that would educate them about modern technology. The International Treaty on Plant Genetic Resources for Food and Agriculture has attempted to remedy this problem, but results have been inconsistent. As a result, "orphan crops", such as teff, millets, cowpeas, and indigenous plants, are important in the countries where they are grown, but receive little investment.[44]
The development and implementation of policies designed to encourage private investments in research and marketing biotechnology that will meet the needs of poverty-stricken nations, increased research on other problems faced by poor nations, and joint efforts by the public and private sectors to ensure the efficient use of technology developed by industrialized nations have been suggested. In addition, industrialized nations have not tested GM technology on tropical plants, focusing on those that grow in temperate climates, even though undeveloped nations and the people that need the extra food live primarily in tropical climates.[39] Many European scientists are disturbed by the fact that political factors and ideology prevent unbiased assessment of the GM technology in some EU countries, with a negative effect on the whole community.[45]
Another important controversy is the possibility of unforeseen local and global effects as a result of transgenic organisms proliferating. The basic ethical issues involved in genetic research are discussed in the article on genetic engineering.
Some critics have raised the concern that conventionally-bred crop plants can be cross-pollinated (bred) from the pollen of modified plants. Pollen can be dispersed over large areas by wind, animals, and insects. In 2007, the U.S. Department of Agriculture fined Scotts Miracle-Gro $500,000 when modified genetic material from creeping bentgrass, a new golf-course grass Scotts had been testing, was found within close relatives of the same genus (Agrostis)[46] as well as in native grasses up to 21 km (13 miles) away from the test sites, released when freshly cut grass was blown by the wind.[47]
GM proponents point out that outcrossing, as this process is known, is not new. The same thing happens with any new open-pollinated crop variety—newly introduced traits can potentially cross out into neighboring crop plants of the same species and, in some cases, to closely related wild relatives. Defenders of GM technology point out that each GM crop is assessed on a case-by-case basis to determine if there is any risk associated with the outcrossing of the GM trait into wild plant populations. The fact that a GM plant may outcross with a related wild relative is not, in itself, a risk unless such an occurrence has negative consequences. If, for example, an herbicide resistance trait was to cross into a wild relative of a crop plant it can be predicted that this would not have any consequences except in areas where herbicides are sprayed, such as a farm. In such a setting the farmer can manage this risk by rotating herbicides.
The European Union funds research programs such as Co-Extra, that investigate options and technologies on the coexistence of GM and conventional farming. This also includes research on biological containment strategies and other measures to prevent outcrossing and enable the implementation of coexistence.
If patented genes are outcrossed, even accidentally, to other commercial fields and a person deliberately selects the outcrossed plants for subsequent planting then the patent holder has the right to control the use of those crops. This was supported in Canadian law in the case of Monsanto Canada Inc. v. Schmeiser.
An often cited controversy is a "Technology Protection" technology dubbed 'Terminator'.[48] This uncommercialized technology would allow the production of first generation crops that would not generate seeds in the second generation because the plants yield sterile seeds. The patent for this so-called "terminator" gene technology is owned by Delta and Pine Land Company and the United States Department of Agriculture. Delta and Pine Land was bought by Monsanto Company in August 2006. Similarly, the hypothetical trait-specific Genetic Use Restriction Technology, also known as 'Traitor' or 'T-gut', requires application of a chemical to genetically modified crops to reactivate engineered traits.[48][49] This technology is intended both to limit the spread of genetically engineered plants, and to require farmers to pay yearly to reactivate the genetically engineered traits of their crops. Genetic Use Restriction Technology is under development by companies including Monsanto and AstraZeneca.
In addition to the commercial protection of proprietary technology in self-pollinating crops such as soybean (a generally contentious issue), another purpose of the terminator gene is to prevent the escape of genetically modified traits from cross-pollinating crops into wild-type species by sterilizing any resultant hybrids. Ironically, the terminator gene technology created a backlash among the same groups that considered outcrossing of GM plants dangerous. They felt the technology would prevent re-use of seed by farmers growing such terminator varieties in the developing world and was ostensibly a means to exercise patent claims.
Hybrid seeds were commonly used in the developed countries long before the introduction of GM crops. Hybrid seeds cannot be saved, so purchasing new seed every year is already a standard agricultural practice.
There are technologies evolving which contain the transgene by biological means and still can provide fertile seeds using fertility restorer functions. Such methods are being developed by several EU research programs, among them Transcontainer and Co-Extra.
Several states of Australia had placed bans on planting GM food crops, beginning in 2003.[50] However, in late 2007 the states of New South Wales and Victoria lifted their bans.[51] Western Australia lifted their state's ban in December 2008,[52] while South Australia continues its ban.[53] Tasmania has extended its moratorium until November 2014.[54] The state of Queensland has allowed the growing of GM crops since 1995 and has never had a GM ban.[55]
In 2005, a standing committee of the government of Prince Edward Island (PEI) in Canada assessed a proposal to ban the production of GMOs in the province. The ban was not passed.[56] As of January 2008, the use of genetically modified crops on PEI was rapidly increasing.[57] Mainland Canada is one of the world's largest producers of GM canola.[58]
As of 2009, Japan has no commercial farming of any kinds of genetically modified food. Consumers have strongly resisted both imports and attempts to grow GMO in the country. Campaigns by consumer groups and environmental groups, such as Consumers Union of Japan and Greenpeace Japan, as well as local campaigns, have been very successful. In Hokkaido, a special bylaw has made it virtually impossible to grow GMOs, as the No! GMO Campaign collected over 200,000 signatures to oppose GMO farming.[59] Consumers Union of Japan participated together with other Japanese NGOs at the Planet Diversity conference in Bonn, Germany on May 12–16, 2008, a global congress on the future of food and agriculture, with a demonstration to celebrate biodiversity, to oppose GMOs. “We don’t only need networks between people, but between people and plants, and people and planet earth,” noted Koketsu Michiyo from CUJ.[60]
Cross-pollination has commonly occurred in Japan, as canola seed (rape seed) is imported from Canada. Around ports and the roads to major food oil companies, imported canola seeds have been found to be GMO varieties, including the Roundup Ready and Liberty Link types not grown in Japan. Nevertheless, activists and local groups, as well as the No! GMO Campaign and others, are alarmed that imported GMOs may harm the biodiversity and cause irreversible damage. A report from the Japanese National Institute for Environmental Studies (NIES) confirms that herbicide-resistant genetically engineered canola plants were identified in five of the six Japanese ports where samples were collected.[61]
A number of Japanese groups have been making submissions to Western Australia’s Review of the Genetically Modified Crops Free Areas Act 2003. These include the Seikatsu Club Consumers’ Cooperative Union and the Consumers Union of Japan. Seikatsu—an umbrella group of 29 Seikatsu Club Consumers’ Co-Operatives—and its oil crushers Okamura Oil Mill Ltd and Yonezawa Oil Co. Ltd., all have non-GE canola policies. The groups stopped importing canola from Canada after the introduction of GE canola, when cross-pollination made it impossible to guarantee GE-free canola from Canada.[62]
The government supports the use of hybrid seeds. However, Monsanto once tried to sell their hybrid seeds of such important crops as wheat and rice via the government. Even though yields would have increased, it would have made the Pakistani population dependent on the seeds of one company. The contract was never given.
In New Zealand, no genetically modified food is grown and no medicines containing live genetically-modified organisms have been approved for use.[63] However, medicines manufactured using genetically modified organisms that do not contain live organisms have been approved for sale, and imported foods with genetically modified components are sold.
In 2004, Mendocino County, California became the first county in the United States to ban the production of GMOs. The measure passed with a 57% majority. In California, Trinity and Marin counties have also imposed bans on GM crops, while ordinances to do so were unsuccessful in Butte, Lake, San Luis Obispo, Humboldt, and Sonoma counties. Supervisors in the agriculturally-rich counties of Fresno, Kern, Kings, Solano, Sutter, and Tulare have passed resolutions supporting the practice.[64]
The Zambian government has launched a campaign to educate and increase awareness of the benefits of biotechnology, including genetically modified crops, in order to change negative public opinion.[39]
The cultivation of Monsanto's MON 810 corn was forbidden in France in February 9, of 2008.[65] It was the only GMO authorized in France. The safeguard measure is taken as far as side effects on human health will be known.
Germany placed a ban on the cultivation and sale of GMO maize in April 2009.[66]
MON 810 (maize) is the only GMO crop cultivated in European soil. The first lines of maize were approved in 1997 and, by 2009, 76,000 hectares of GM maize were grown in Spain (20% of Spain's maize production). Smaller amounts were produced in the Czech Republic, Portugal and Germany.[67] However, in addition to France and Germany, other European countries that have placed bans on the cultivation and sale of GMOs include Austria, Hungary, Greece, and Luxemburg.[68] Ireland has also banned GMO cultivation, and has instituted a voluntary label for GMO-free food products.[69] Poland has also has tried to institute a ban, with backlash from the European Commission.[70] Bulgaria effectively banned cultivation of genetically modified organisms on March 18, 2010.[71]
On 2 March 2010 another species of GMO, a potato named Amflora, was approved for cultivation for industrial applications in the European Union market by the European Commission.[72] On 13 July 2010, the European Commission issued a recommendation that in future individual states in the EU should be able to ban the growing of specific GM crops that had been scientifically approved at the EU level. A ban could be justified on cultural, economic or ethical grounds.[73][74] The EU approval process for imports of GM crops and labelling of GM food products remained in place.[75][76]
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