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Genetically modified organism
9 k6 p8 b0 s( o* O# @' xA 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. Some GMOs contain no DNA from other species and are therefore not transgenic but cisgenic.
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8 u3 S4 p2 `! S2 t% ZContents [hide]
. F) _) G! [1 T# A' Q' a1 Production
( h0 e7 a5 |! G9 x( h; a( L, T2 History 9 E4 H; _! A0 Z# C
3 Uses
/ o9 A6 w( o$ n1 w' I3.1 Detection
2 Z3 ]* `& K m( z9 f9 M7 n# ~3.2 Transgenic microbes
4 O" j& s* T! |5 R( t3.3 Transgenic animals 0 G& p. T" C4 [2 ?& i
3.4 Gene therapy . y ?- O! `9 e3 x! _# _
3.5 Transgenic plants
G" R9 Y6 u7 G+ W2 z3.6 Cisgenic plants
0 @) m5 [; T+ G) e4 Controversy # }$ I- D* A0 O
4.1 Governmental support and opposition ' q4 r8 a: C( @' u
4.1.1 United States 7 b J3 |2 q' Z: Q9 n1 B
4.1.2 New Zealand
_( @ B( k1 d9 a$ t" d4.1.3 Canada
; Y I8 h5 w0 W7 j4.1.4 Australia 4 N& T# T0 @4 b! E0 d, Q1 `
4.1.5 Zambia : s% [# M* [( f6 ^8 {! W
4.2 Cross-pollination concerns 4 {9 g& o* }( K: i
4.3 "Terminator" and "traitor"
! V! L) q* W" }5 L2 o! x( h5 See also * l% a* T7 ]: m+ j6 J* `
6 References
7 l) k: h+ \: v5 p. e7 External links
) ]& ^1 A; F5 X. o. O7.1 General
8 t, [2 }: Q) C! d3 x7.2 Transgenic animals 7 d. f. R* V2 L
7.3 Transgenic plants
% {6 T4 I3 z iProduction; [- p" [) O4 I: b' E+ n4 X- T
Further information: Horizontal Gene Transfer and Transformation (genetics)2 ]8 o* R6 d, }3 T% c% p
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]' F+ _# }& y% M3 J
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History
/ z% R- K) u# ^+ J- DThe 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, i.e., E .coli expressing a 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]
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" b4 p, s3 C7 A% q( W; K3 xIn 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 was dropped.
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Uses
' w' o* {8 w, P' S: VGMOs have widespread applications. They 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.
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To date the broadest 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 Monsanto according to the company. 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.; K/ z# n# L) W9 [
( Z/ Z2 R$ ?0 ^$ C- W% |; U) [! C, kIn 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 17 million acres (69,000 km2) of triple-stack corn in 2007, and it is estimated the product could be planted on 45 million to 50 million acres (200,000 km2) by 2010. In the cotton market, Bollgard II with Roundup Ready Flex was planted on nearly 3 million acres (12,000 km2) of U.S. cotton in 2007.4 ^+ I& X) c9 B
6 x% Y! i+ \+ tRapid growth in the total area planted is measurable by Monsanto's growing share. On January 3, 2008, Monsanto Company (MON.N) said its quarterly profit nearly tripled, helped by strength in its corn seed and herbicide businesses, and raised its 2008 forecast.[8]& D/ t- z5 H* ?4 G% n6 K; `
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According to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA), of the approximately 8.5 million farmers who grew biotech crops in 2005, some 90% were resource-poor farmers in developing countries. These include some 6.4 million farmers in the cotton-growing areas of China, an estimated 1 million small farmers in India, subsistence farmers in the Makhathini flats in KwaZulu Natal province in South Africa, more than 50,000 in the Philippines and in seven other developing countries where biotech crops were planted in 2005.[9]+ f8 m! T+ D/ K( P) d" y8 [* y
( |% K: T& S5 Q# _"The Global Diffusion of Plant Biotechnology: International Adoption and Research in 2004", a study by Dr. Ford Runge of the University of Minnesota, estimates the global commercial value of biotech crops grown in the 2003–2004 crop year at US$44 billion.[10]
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In the United States the United States Department of Agriculture (USDA) reports on the total area of GMO varieties planted. According to National Agricultural Statistics Service, the States published in these tables represent 81-86 percent of all corn planted area, 88-90 percent of all soybean planted area, and 81-93 percent of all upland cotton planted area (depending on the year). See more on the extent of adoption at: http://www.ers.usda.gov/Data/BiotechCrops/.
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USDA does not collect data for global area. Estimates are produced by the International Service for the Acquisition of Agri-biotech Applications (ISAAA) and can be found in the report, Global Status of Commercialized Transgenic Crops: 2007.[11]) G7 }7 B1 E0 f! j
& O2 b$ T$ s. _; QTransgenic animals are also becoming useful commercially. 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.[12]
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; `8 Q" ~% w* {8 k4 d8 T" rDetection# W* Y6 {$ |6 `
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 [13], 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.
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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.3 [0 V4 y, H' ~
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Transgenic microbes
% l8 W s' @% v3 z% CBacteria were the first organisms to be modified in the laboratory, due to their simple genetics.[14] These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine.[15]' n3 R$ Q! E3 \7 y
$ N- U; v9 b1 P3 I2 Q' JGenetically modified bacteria are used to produce the protein insulin to treat diabetes.[16] Similar bacteria have been used to produce clotting factors to treat haemophilia,[17] and human growth hormone to treat various forms of dwarfism.[18][19] These recombinant proteins are safer than the products they replaced, since the older products were purified from cadavers and could transmit diseases.[20] Indeed the human-derived proteins caused many cases of AIDS and hepatitis C in haemophilliacs and Creutzfeldt-Jakob disease from human growth hormone.[20][21]
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; M: y5 G" S% P% h4 k+ wFor instance, the bacteria which cause tooth decay are called Streptococcus mutans. These bacteria consume leftover sugars in the mouth, producing lactic acid that corrodes tooth enamel and ultimately causes cavities. Scientists have recently modified Streptococcus mutans to produce no lactic acid.[22] These transgenic bacteria, if properly colonized in a person's mouth, could reduce the formation of cavities.[23] Transgenic microbes have also been used in recent research to kill or hinder tumors, and to fight Crohn's disease.[citation needed] Genetically modified bacteria are also used in some soils to facilitate crop growth, and can also produce chemicals which are toxic to crop pests.; ~6 s/ G% @7 v. ^8 I' a, X
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Transgenic animals' R9 x4 }5 ^$ ~& B/ L) A. c
Transgenic animals are used as experimental models to perform phenotypic tests with genes whose function is unknown. Genetic modification can also produce animals that are susceptible to certain compounds or stresses for testing in biomedical research.[24] Other applications include the production of human hormones such as insulin., q4 V* N4 ?6 |( k- ^; J9 x
2 a B8 t& k! n. XIn biological research, transgenic fruit flies (Drosophila melanogaster) are model organisms used to study the effects of genetic changes on development.[25] 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. Transgenic mice are often used to study cellular and tissue-specific responses to disease. This is possible since mice can be created with the same mutations that occur in human genetic disorders, the production of the human disease in these mice then allows treatments to be tested.[26]
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Cnidarians such as Hydra have become attractive model organisms to study the evolution of immunity. For analytical purposes an important technical breakthrough was the development of a transgenic procedure for generation of stably transgenic hydras by embryo microinjection.[27]
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+ U U( `6 [8 W) c( k4 h$ d; {Transgenesis in fish with promotors driving an over-production of growth hormone (GH) has resulted in dramatic growth enhancement in several species, including salmonids, carps and tilapias. These fish have been created for use in the aquaculture industry to increase meat production and, potentially, reduce fishing pressure on wild stocks. None of these GM fish have yet appeared on the market, mainly due to the concern expressed among the public of the fish's potential negative effect on the ecosystem should they escape from rearing facilities.& G& s; _) N3 g
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& {9 `& P1 o& y, g( m9 b! n5 vGene therapy
! R1 {2 k! M/ g1 ?Gene therapy,[28] 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,[29] and treatments are being developed for a range of other currently incurable diseases, such as cystic fibrosis,[30] sickle cell anemia,[31] and muscular dystrophy.[32]. 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.
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- {4 g9 I2 b |2 |/ ]Transgenic plants
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) m; E# G, {, h+ m+ gKenyans examining insect-resistant transgenic Bt cornTransgenic plants have been engineered to possess several desirable traits, including resistance to pests, herbicides or harsh environmental conditions, improved product shelflife, 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, and to produce the Bt toxin, a potent insecticide.
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) r2 n" j, o/ P- tBt-maize is a corn that has been genetically modified by splicing the toxin-producing gene from bacteria into the DNA sequence of the corn in order to sicken or kill insects that try to consume it. While some genetically modified crops are more nutritious because they contain these extra vitamins and minerals, they will not cure all of the malnutrition-related ailments in the world and should only be a supplement to a balanced diet. [33]
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Cisgenic plants& A: l1 ]# Q5 }3 d' h# k
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 reality, customers would have to eat twelve bowls of rice a day in order to meet the recommended levels of Vitamin A. 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. [34]# U5 K w: C; ]2 y: h" D. e
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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 programmes 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.
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Controversy# w9 J G" O4 t9 S4 T
See also: Genetically modified food controversies
# h- ^0 u5 ^' g5 N$ P( y The examples and perspective in this article may not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page. # L# t5 ?- x8 k7 Y" l2 ?
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The use of GMOs has sparked significant controversy in many areas.[35] 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.
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The safety of GMOs in the foodchain has been questioned, with concerns such as the possibilities that GMOs could introduce new allergens into foods, or contribute to the spread of antibiotic resistance.[36] Although scientists have assured consumers of the safety of these types of crops, consumption has been discouraged in many countries by food and environmental activist groups who protest GM crops, claiming they are unnatural and therefore unsafe. [37] This has led to the adoption of laws and regulations that require safety testing of any new organism produced for human consumption.[38]' H9 r5 I! S3 w' o. R
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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]
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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 true 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. [40]; r" K; a$ ?6 L
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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.
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& j7 ]' V2 C$ H [Some groups believe that underdeveloped 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 tef, millets, cowpeas, and indigenous plants, are important in the countries where they are grown, but receive little investment.[41] 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. [42]9 z) I. H9 A& [0 ]- v: G
( p) |8 r9 ]4 P, c, S FAnother 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.. `; p6 p5 `. F% o$ S, C
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# x1 l9 k2 z! c! NGovernmental support and opposition
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United States
/ [" k Q/ `6 `5 i; F5 Z# }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.[43][citation needed]" X, X2 p+ D. S8 E2 P- @: k
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New Zealand
* D4 g6 @: ] k! M' c* _In New Zealand, no genetically modified food is grown and no medicines containing live genetically-modified organisms have been approved for use.[44] However, medicines manufactured using genetically modified organisms that do not contain live organisms have been approved for sale.
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6 G' N i2 k5 n0 NCanada# g# B0 K, Q s( _5 B% C! w
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.[45] As of January 2008, the use of genetically modified crops on PEI was rapidly increasing.[46] Mainland Canada is one of the world's largest producers of GM canola.[citation needed]
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Australia
7 R7 j( _2 `4 qSeveral states of Australia had placed bans on planting GM food crops, beginning in 2003.[47] However, in late 2007 the states of New South Wales and Victoria lifted their bans.[48] Western Australia lifted that state's ban in December 2008,[49] while South Australia continues its ban.[50] Tasmania has extended its moratorium until November 2014.[51] The state of Queensland has allowed the growing of GM crops since 1995 and has never had a GM ban.[52]
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Zambia
! [6 n5 o3 N3 ?) l+ UThe 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. [53]
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5 [! N3 I1 f- u: MCross-pollination concerns5 @ P+ Y7 m4 o4 I+ F M9 _
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 $500,000 when modified genetic material from creeping bentgrass, a new golf-course grass Scotts had been testing, was found within close relatives of the same genus (Agrostis)[54] as well as in native grasses up to 21 km (13 miles) away from the test sites, released when freshly cut grass was blown by the wind. [55]' d9 [$ d; U. h2 c5 k0 f* U
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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, a 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.
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; J2 ~1 x) D) Z8 y; FThe European Union funds research programmes such as Co-Extra, that investigate options and technologies on the co-existence of GM and conventional farming. This also includes research on biological containment strategies and other measures, to prevent outcrossing and enable the implementation of co-existence.! C5 K C3 t% d+ ?' d
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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.
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"Terminator" and "traitor"
; ?: L/ u& z1 H6 X$ ~& S3 pAn often cited controversy is a "Technology Protection" technology dubbed 'Terminator'.[56] This yet-to-be-commercialized 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 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.[57] 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. Traitor is under development by companies including Monsanto and AstraZeneca.
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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. The terminator gene technology created a backlash amongst those who 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. Use of the terminator technology would also prevent "volunteers", or crops that grow from unharvested seed, a major concern that arose during the Starlink debacle. 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 programmes, among them Transcontainer and Co-Extra.- M0 S0 t/ F! O+ C8 e T3 Q
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See also
7 y7 \# P, J# }. [* H9 THorizontal Gene Transfer: The movement of genes between different species occurs often naturally. ; g( g: e, w) L2 H
Genetically modified food
2 i. Z# [8 }3 z/ p, |+ aLMO (Living Modified Organism)
! A$ \ t3 S+ t1 R. J- X5 YTransgene 4 E# [) u( V8 C1 l) {% N
Gene flow
8 h3 e8 S( \4 P. K: \, LOrganic farming
8 a$ [! N% @" P# Y* PPermaculture & v" B6 {2 \: T) X
Organic food " o% z2 F y& J" E4 Z5 O* U$ k" o
GM food controversies
4 e+ ^4 |1 D5 c* ~( k0 f9 f6 |GloFish 1 q/ i+ S+ W" z
Chimera (genetics) 2 V. A1 i$ k! U: v
Dolly the sheep
2 [7 b" m( _: v( I. aHerman the Bull
$ ]7 I+ N* c) N7 s& ~6 }( L0 |6 bIce-minus bacteria
+ [/ ~3 L4 F$ l' N, T5 f1 mBioSteel . R) d4 `; }9 o
Gene pool
# H9 Z/ ~" B# ZGenetic pollution
& h2 V3 J* _" _* IGenetic erosion + m* A. a9 I! n8 V
Smart breeding - |$ z* H1 s8 F$ K4 k% `0 ~
Synthetic Biology |
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发表于 2009-5-24 21:21
