Genetically modified food

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Genetically modified (GM) foods are made from plants and animals that have been given specific traits through genetic engineering, unlike plants and animals developed through the conventional genetic modification of selective breeding (plant breeding and animal breeding). Some authorities consider genetically engineered crops to be a subset of genetically modified crops, as conventionally bred crops undergo genetic modification and may pose unintended health consequences.[1] GM foods were first put on the market in the early 1990s. Typically, genetically modified foods are plant products: soybean, corn, canola, and cotton seed oil, but animal products have been proposed. For example, in 2006 a pig engineered to produce omega-3 fatty acids through the expression of a roundworm gene was controversially[2][3] proposed.[4]


[edit] Method

Genetic engineering begins with the identification and isolation of a gene which expresses a desirable trait. Then a recipient plant or animal is selected, and the gene is inserted and incorporated into its genome through a vector such as a bacterium (commonly agrobacterium), through a gene gun shooting an elemental particle covered in plasmid DNA, electroporation, or a virus. Once part of the recipient, the newly inserted gene is indistinguishable from its native genes and will be used by the recipient like any other gene. If a strawberry plant is given a gene from an alpine plant that is highly tolerant of cold, it may improve the strawberry's resistance to frost, or if a pig receives some genes from a spinach genome which barely has any fat, it will most likely reduce the fat content of the meat.

[edit] Development

The first commercially grown genetically modified whole food crop was the tomato puree (called FlavrSavr), which was made more resistant to rotting by Californian company Calgene.[5] Calgene was allowed to release it in 1994 without any special labeling.[6] It was welcomed by consumers who purchased the fruit at two to five times the price of regular tomatoes. However, production problems[5] and competition from a conventionally bred, longer shelf-life variety prevented the product from becoming profitable. A variant of the Flavr Savr was used by Zeneca to produce tomato paste which was sold in Europe during the summer of 1996.[7] The labeling and pricing were designed as a marketing experiment, which proved, at the time, that European consumers would accept genetically engineered foods.

Currently, there are a number of foods of which a genetically modified version exists.

Food Properties of the genetically modified variety Trade name Company Modification Percent in UK Percent in world
Soybeans Resistant to herbicides Roundup Ready, Monsanto Herbicide resistant gene taken from bacteria inserted into soy bean 89% TBA
Corn, field Resistant to pesticides (tolerating crop spray - this way a farmer can use amounts of pesticides which would normally kill the plant, without harming it) Roundup Ready, Monsanto New gene added/transferred into plant genome 60% TBA
Cotton Pest-resistant cotton TBA New gene added/transferred into plant genome 83% TBA
Hawaiian Papaya Variety is resistant to the Papaya Ringspot Virus. TBA New gene added/transferred into plant genome +50% TBA
Tomatoes Variety that does not rot (degrade) as fast - the genetically modified (gm) tomatoes do not produce the enzyme that normally causes tomatoes to rot and degrade. E.g. FlavrSavr First genetically modified tomatoes contained genes that made them resistant to antibiotics. After concern from doctors and the medical community, tomatoes were then genetically modified in a different way. Taken off the market due to consumer protest. TBA
Potatoes TBA TBA
Rapeseed (Canola) Resistance to certain pesticides (tolerating crop spray) Bt New gene added/transferred into plant genome 75% TBA[8]
Sugar cane Resistance to certain pesticides (tolerating crop spray) TBA New gene added/transferred into plant genome TBA TBA
Sugar beet Resistance to certain pesticides (tolerating crop spray) Roundup Ready, Monsanto New gene added/transferred into plant genome TBA TBA
Sweet corn Produces its own insecticide (a toxin to insects, so insect attacks are less likely) Bt corn Gene from the bacteria Bacillus thuringiensis added to the plant. TBA TBA
Rice Genetically modified to contain high amounts of Vitamin A (beta-carotene) "Golden rice" Three new genes implanted: two from daffodils and the third from a bacterium TBA TBA

In addition, various micro-organisms have been genetically engineered to produce aspartame, amino acids, and various chemicals. [9]

[edit] Growing GM crops

Between 1997 and 2005, the total surface area of land cultivated with GMOs had increased by a factor of 50, from 17,000 km2 (4.2 million acres) to 900,000 km2 (222 million acres), of which 55 percent were Brazil.

Although most GM crops are grown in North America, in recent years there has been rapid growth in the area sown in developing countries. For instance in 2005 the largest increase in crop area planted to GM crops (soybeans) was in Brazil (94,000 km2 in 2005 versus 50,000 km2 in 2004.)[10] There has also been rapid and continuing expansion of GM cotton varieties in India since 2002. (Cotton is a major source of vegetable cooking oil and animal feed.) It is predicted that in 2008/9 32,000 km2 of GM cotton will be harvested in India (up more than 100 percent from the previous season). Indian national average cotton yields of GM cotton were seven times lower in 2002, because the parental cotton plant used in the genetic engineered variant was not well suited to the climate of India and failed. The publicity given to transgenic trait Bt insect resistance has encouraged the adoption of better performing hybrid cotton varieties, and the Bt trait has substantially reduced losses to insect predation. Though controversial and often disputed, economic and environmental benefits of GM cotton in India to the individual farmer have been documented.[11][12]

In 2003, countries that grew 99% of the global transgenic crops were the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), China (4%), and South Africa (1%).[13] The Grocery Manufacturers of America estimate that 75% of all processed foods in the U.S. contain a GM ingredient[14] . In particular, Bt corn, which produces the pesticide within the plant itself, is widely grown, as are soybeans genetically designed to tolerate glyphosate herbicides. These constitute "input-traits" are aimed to financially benefit the producers, have indirect environmental benefits and marginal cost benefits to consumers.

In the US, by 2006 89% of the planted area of soybeans, 83% of cotton, and 61% maize were genetically modified varieties. Genetically modified soybeans carried herbicide-tolerant traits only, but maize and cotton carried both herbicide tolerance and insect protection traits (the latter largely the Bacillus thuringiensis Bt insecticidal protein). In the period 2002 to 2006, there were significant increases in the area planted to Bt protected cotton and maize, and herbicide tolerant maize also increased in sown area.[15]

[edit] Crop yields

Several studies have found that genetically modified varieties of plants do not produce higher yields than normal plants.[16]

A study from Berkeley says that despite claims from the biotech industry and academic researches, there is no indication that biotechnology will solve the shortcomings of industrial agriculture. Compared to the novel and untested crop systems that biotech corporations are pushing as the only solution to food security problems, organic farming has many advantages. The majority of genetically engineered crops currently in cultivation do not appear to show higher yields. For example, contrary to claims by Monsanto, a recent study by Dr. Charles Bendrook, the former director of the Board on Agriculture at the National Academy of Sciences, indicates that genetically engineered Roundup Ready soybeans do not increase yields (Bendrook, 1999). The report reviewed over 8,200 university trials in 1998 and found that Roundup Ready soybeans yielded 7-10% less than similar natural varieties. In addition, the same study found that farmers used 5-10 times more herbicide (Roundup) on Roundup Ready soybeans than on conventional ones. The only reason farmers seem to prefer Roundup Ready soybeans is because they simplify management of large chemically-intensive farms by allowing them, for example, to spray larger doses of herbicides from planes on crops engineered to be resistant to the particular herbicide. Applications of biotechnology continue the legacy of industrial agricultural with monocultures and high energy and chemical inputs. [17]

[edit] Coexistence and traceability

In many parts of the world, such as the European Union, Japan, Malaysia and Australia, consumers demand labeling so they can exercise choice between foods that have genetically modified, conventional or organic origins.[18][19] This requires a labeling system as well as the reliable separation of GM and non-GM organisms at production level and throughout the whole processing chain.[18][19] Research suggests that this may prove impossible, one reason why GM opponents use the 'genie out of a bottle' analogy.

For traceability, the OECD has introduced a "unique identifier" which is given to any GMO when it is approved. This unique identifier must be forwarded at every stage of processing.

Many countries have established labeling regulations and guidelines on coexistence and traceability. Research projects such as Co-Extra, SIGMEA and Transcontainer are aimed at investigating improved methods for ensuring coexistence and providing stakeholders the tools required for the implementation of coexistence and traceability.

[edit] Controversy

Some scientists[20] argue that there is more than enough food in the world and that the hunger crisis is caused by problems in food distribution and politics, not production, so people should not be offered food that may carry some degree of risk.[21][22]

A media firestorm erupted in 1999 when scientist Árpád Pusztai found that consumption of potatoes genetically modified to contain lectin had negative intestinal effects on rats. He felt he had a duty to speak out, "just to inject some caution into this business". He says, "Make no mistake, this is an irreversible technology. It is no good 50 years later to say: 'We should have known.'" [23] Because of the controversial nature of his research, the data paper was seen by six reviewers - three times the usual number. Five gave it the green light. The paper - which used data held by Ewen and so was not subject to veto by James - showed that rats fed on potatoes genetically modified with the snowdrop lectin had unusual changes to their gut tissue compared with rats fed on normal potatoes. [24][25] It has been criticised on the grounds that the unmodified potatoes were not a fair control diet.[26] As a consequence, he became the victim of a smear campaign, but was eventually vindicated.[27]

[edit] Economic and political effects

  • Many proponents of some current genetic engineering techniques claim that it will lower pesticide usage and has brought higher yields and profitability to many farmers, including those in developing nations.[28] A few genetic engineering licenses allow farmers in less economically developed countries to save seeds for next year's planting.[citation needed]
  • In August 2003, Zambia cut off the flow of Genetically Modified Food (mostly maize) from UN's World Food Programme. This left a famine-stricken population without food aid.
  • In December 2005 the Zambian government changed its mind in the face of further famine and allowed the importation of GM maize.[29] However, the Zambian Minister for Agriculture Mundia Sikatana has insisted that the ban on genetically modified maize remains, saying "We do not want GM (genetically modified) foods and our hope is that all of us can continue to produce non-GM foods."[30][31]
  • In April 2004 Hugo Chávez announced a total ban on genetically modified seeds in Venezuela.[32]
  • In January 2005, the Hungarian government announced a ban on importing and planting of genetic modified maize seeds, although these were agreed authorized by the EU.[33]
  • On August 18, 2006, American exports of rice to Europe were interrupted when much of the U.S. crop was confirmed to be contaminated with unapproved engineered genes, possibly due to accidental cross-pollination with conventional crops.[34]

[edit] Intellectual property

Enforcement of patents on genetically modified plants is often contentious, especially because of gene flow. In 1998, 95-98 percent of about 10 km2 planted with canola by Canadian farmer Percy Schmeiser were found to contain Monsanto's patented Roundup Ready gene although Schmeiser had never purchased seed from Monsanto.[35] The initial source of the plants was undetermined, and could have been through either gene flow or intentional theft. However, the overwhelming predominance of the trait implied that Schmeiser must have intentionally selected for it. The court determined that Schmeiser had saved seed from areas on and adjacent to his property where Roundup had been sprayed, such as ditches and near power poles.[36]

Although unable to prove direct theft, Monsanto sued Schmeiser for piracy since he knowingly grew Roundup Ready plants without paying royalties(Ibid). The case made it to the Canadian Supreme Court, which in 2004 ruled 5 to 4 in Monsanto’s favor.[35][36] The dissenting judges focused primarily on the fact that Monsanto's patents covered only the gene itself and glyphosate resistant cells, and failed to cover transgenic plants in their entirety. All of the judges agreed that Schmeiser would not have to pay any damages since he had not benefited from his use of the genetically modified seed.

In response to criticism, Monsanto Canada's Director of Public Affairs stated that "It is not, nor has it ever been Monsanto Canada's policy to enforce its patent on Roundup Ready crops when they are present on a farmer's field by accident...Only when there has been a knowing and deliberate violation of its patent rights will Monsanto act."[37] Currently Percy Schmeiser spends a large amount of his time traveling and speaking about how Monsanto ruined his career as a farmer. He also talks about the possible harms of genetic modification and why others in addition to himself should be protesting it.

[edit] Future developments

Future envisaged applications of GMOs are diverse and include drugs in food, bananas that produce human vaccines against infectious diseases such as Hepatitis B,[38] metabolically engineered fish that mature more quickly, fruit and nut trees that yield years earlier, foods no longer containing properties associated with common intolerances, and plants that produce new plastics with unique properties.[39] There are natural non genetically engineered alternatives to plastic being considered such as liquid wood [40] While their practicality or efficacy in commercial production has yet to be fully tested, the next decade may see exponential increases in GM product development as researchers gain increasing access to genomic resources that are applicable to organisms beyond the scope of individual projects. Safety testing of these products will also, at the same time, be necessary to ensure that the perceived benefits will indeed outweigh the perceived and hidden costs of development. Plant scientists, backed by results of modern comprehensive profiling of crop composition, point out that crops modified using GM techniques are less likely to have unintended changes than are conventionally bred crops.[41][42]

[edit] Health Risks

Currently there are only a few dozen peer reviewed studies completed on the health effects of genetically modified foods. The results of many of these studies strongly challenges the industry and government standard of substantial equivalence.

[edit] Gene transfer

As of January 2009 there has only been one human feeding study conducted on genetically modified foods. The study involved seven human volunteers who had their large intestines removed. These volunteers were to eat GM soy to see if the DNA of the GM soy transferred to the human gut bacteria. Researchers identified that three of the seven volunteers had transgenes from GM soy transferred into their gut bacteria.[43]

"This transgene was stable inside the bacteria and appeared to produce herbicide-tolerant protein... In the only human feeding study ever conducted on GM crops, long standing assumptions that genes would not transfer to human gut bacteria were overturned. The findings should prompt immediate comprehensive follow-up tests to determine the implications for health among both the general population and at-risk groups."[44]

[edit] Allergies

Since 2004, some cotton workers in India have experienced allergic reactions to only Bt cotton, and not to other conventional varieties. The longer the workers were exposed to the genetically modified Bt cotton, the more severe their symptoms were. An investigation concluded that reactions included: "mild to severe itching; in severe cases, eyes also became red, and swollen"[45] One doctor reported that he had seen approximately 150 cases of allergies to Bt Cotton in 2005, and another 100 in 2004. [46]

In the mid 1990's Pioneer Hi-Bred began to genetically modify a soybean that would take a gene from a Brazil nut in the hopes that soy would increase the production of the amino acid methionine. While this particular new crop was being designed for animal feed, as the case of StarLink corn clearly showed, that food only for animal consumption will undoubtedly enter the human food supply. Pioneer Hi-Bred decided to test the new GM soybean with the Brazil nut gene for allergens as many people are allergic to Brazil nuts. To the company's surprise in three separate tests (radioallergosorbent testing, immunoblotting, and skin-prick testing), all studies showed that individuals allergic to Brazil nuts were also allergic to the new GM soybean.[47] "In trying to build a better soybean the company had made a potentially deadly one."[48]

In 1999 soy allergies in the United Kingdom increased from 10%-15% in a single year. Coincidentally, GM soy entered the UK shortly before 1999. One study using skin prick test showed that of the 49 subjects, 13 individuals experienced a positive reaction to non-GM soy, 8 individuals reacted to the GM soybeans, and "one patient had a positive skin test result to GMO soybeans only."[49]

[edit] New Diseases

In the 1980s one brand of L-Tryptophan that was genetically engineered and created by Showa Denko in Japan, caused a deadly epidemic in the United States. Symptoms of those individuals whom contracted this disease, later named Eosinophilia-myalgia syndrome (EMS), included: swelling, coughs, rashes, physical weakness, pneumonia, breathing difficulties, hardening of skin, mouth ulcers, nausea, shortness of breath, muscle spasms, visual problems, hair loss, difficulty with concentration, memory and paralysis.[50] Discovering the cause of EMS required numerous coincidences which suggest that adverse reactions to genetically engineered foods may be difficult to identify. In 1984, progressively the more genes that Showa Denko added to the L-Tryptophan supplement corresponded to the higher levels of contamination. "The final strain, which caused the most illness, contained five separate transgenes.".[51]

Some individuals from the FDA disputed that it was the genetically engineered L-Tryptophan that was to blame, but rather tryptophan itself; however, this theory was unsubstantiated. According to Edwin Kilbourne, who investigated EMS with the Center for Disease Control (CDC), if L-Tryptophan itself was to blame, "all tryptophan products of equal dose produced from different companies should have the same effect."[52] However, Kilbourne insists that there is currently no evidence to support this claim. According to the CDC, the genetically engineered supplement killed about 100 people, 1500 became permanently disabled and caused between 5,000 and 10,000 to fall sick.

[edit] See also

[edit] References

  1. ^ NRC. (2004). Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects. National Academies Press. Free full text.
  2. ^ Kang JX et al. (2007). "Why the omega-3 piggy should go to market". Nature Biotechnology 25 (5): 505–506. Retrieved on 2009-03-29. 
  3. ^ Fiester, A. (2006). "Why the omega-3 piggy should not go to market". Nature Biotechnology 24: 1472–1473. Retrieved on 2009-03-29. 
  4. ^ Lai L et al. (2006). "Generation of cloned transgenic pigs rich in omega-3 fatty acids". Nature Biotechnology 24 (4): 435�436. Retrieved on 2009-03-29. 
  5. ^ a b Martineau, Belinda (2001). First Fruit: The Creation of the Flavr Savr Tomato and the Birth of Biotech Foods. McGraw-Hill. pp. 269. ISBN 978-0071360562. 
  6. ^ FDA Consumer Letter (September 1994): First Biotech Tomato Marketed
  7. ^ GEO-PIE Project - Cornell University[1]
  8. ^ Canadian Organic Canola growers claim their crop has been contaminated by cross pollination of GMO canola pollen and have subsequently launched litigation against Monsanto for destroying their ability to grow non-GMO canola Canadian Organic Association
  9. ^ Smith, Jeffrey. Genetic Roulette.
  10. ^ Need a more specific citation for this data than the ISAAA homepage.
  11. ^ Economic Impact of Genetically Modified Cotton in India
  12. ^ Comparing the Performance of Official and Unofficial Genetically Modified Cotton in India
  13. ^ Genetically Modified Foods and Organisms
  14. ^ Genetic Engineering: The Future of Foods?
  15. ^ Adoption of Genetically Engineered Crops in the U.S. USDA ERS July 14, 2006
  16. ^ [2]
  17. ^
  18. ^ a b Northwestern Journal of Technology and Intellectual Property Paper on: "Consumer Protection" Consumer Strategies and the European Market in Genetically Modified Foods Quote: The recent Trans Atlantic Consumer Dialogue (TACD) Statement on the WTO decision makes this clear: "clearly consumers' preference for non-GM food is the true engine of the market collapse for American crops." and For instance, Evenson notes that the politicization of GMOs is not merely a question of labeling as information, but unlabeled GM products as catalysts in the "globalization backlash."
  19. ^ a b CBC Identifying genetically modified products. Quote: Yet as seen in this report from CBC's Marketplace, no such labeling law exists in Canada despite numerous surveys indicating up to 90 per cent of Canadians want mandatory labeling of GM food. Canada's leading national consumer group does not support mandatory labeling. It appeared to reverse its stance on December 3, 2003:
  20. ^ Raney, Terri, and Prahbu Pingali. "Sowing A Gene Revolution." Scientific American September 2007. 11 September 2008 <>.
  21. ^ Lappe FM, Collins J, Rosset P, and Esparza LFrances Moore Lappé ; Joseph Collins; Peter Rosset. With Luis Esparza. (1998). World Hunger: Twelve Myths. Grove Press. pp. 224. ISBN 978-0802135919. 
  22. ^ Boucher Dedited by Douglas H. Boucher. (1999). The Paradox of Plenty: Hunger in a Bountiful World. Food First. pp. 342. ISBN 978-0935028713. 
  23. ^
  24. ^
  25. ^
  26. ^ Ewen SW, Pusztai A (October 1999). "Effect of diets containing genetically modified potatoes expressing Galanthus nivalis lectin on rat small intestine". Lancet 354 (9187): 1353–4. doi:10.1016/S0140-6736(98)05860-7. PMID 10533866. 
  27. ^
  28. ^
  29. ^
  30. ^
  31. ^
  32. ^
  33. ^
  34. ^ Agriculture Department Probes Rice Flap: NPR
  35. ^ a b Munzer, Stephen R. (2006). Plants, Torts, and Intellectual Property. Oxford University Press. pp. 1-30. 
  36. ^ a b Federal court of Canada. Monsanto Canada Inc. v. Schmeiser Date: 20010329 Docket: T-1593-98 Retrieved 26 March 2006.
  37. ^ Schubert, Robert: "Schmeiser Wants to Take It to The Supreme Court", CropChoice News, September 9, 2002
  38. ^ Kumar, G. B. Sunil; T. R. Ganapathi, C. J. Revathi, L. Srinivas and V. A. Bapat (October 2005). "Expression of hepatitis B surface antigen in transgenic banana plants". Planta 222: 484–493. doi:10.1007/s00425-005-1556-y. 
  39. ^ van Beilen, Jan B.; Yves Poirier (May 2008). "Harnessing plant biomass for biofuels and biomaterials:Production of renewable polymers from crop plants". The Plant Journal 54 (4): 684–701. doi:10.1111/j.1365-313X.2008.03431.x. 
  40. ^
  41. ^ Proteomic profiling and unintended effects in genetically modified crops, Sirpa O. Kärenlampi and Satu J. Lehesranta 2006
  42. ^ Hierarchical metabolomics demonstrates substantial compositional similarity between genetically modified and conventional potato crops, G S Catchpole and others PNAS October 4, 2005 vol. 102 no. 40 14458-14462
  43. ^ Netherwood et al, "Assessing the survival of transgenic planic plant DNA in the human gastrointestinal tract," Nature Biotechnology 22 (2004):2.
  44. ^ Smith, Jeffery. Genetic Roulette: The Documented Health Risks of Genetically Engineered Foods, p.130, 2007
  45. ^ Ashish Gupta, "Impact of Bt Cotton on Farmers' Health (in Barwani and Dhar District of Madhya Predesh)," Investigation Report, October-December 2005.
  46. ^ Ashish Gupta, "Impact of Bt Cotton on Farmers' Health (in Barwani and Dhar District of Madhya Predesh)," Investigation Report, October-December 2005.
  47. ^ Julie A. Nordlee, "Identification of Brazil-Nut Allergen in Transgenic Soybeans," New England Journal of Medicine, 334 (1996):688-692.
  48. ^ Rick Weiss, "Biotech Food Raises a Crop of Questions," Washington Post, August 15, 1999: A1
  49. ^ Hye-Yung Yum, Soo-Young Lee, Kyung-Eun Lee, Myung-Hyun Sohn, Kyu-Earn Kim, "Genetically Modified and Wild Soybeans: An Immunologic comparison," Allergy and Asthma Proceeding 26, no.3 (May-June 2005): 210-216(7).
  50. ^ Smith, Jeffrey M. "Genetic Roulette: The Documented Health Risks of Genetically Engineered Foods" 2007: 60-61, Yes! Books, Iowa, USA
  51. ^ A.N. Mayeno and G.J. Gleich, eds, "Ecsinophilia-Myalgia Syndrom and Tryptophan Production: A cautionary Tale." Trends Biotechnol 12 (1994): 346-352; as quoted in William E. Crist, "The Toxic L-Tryptophan Epidemic"
  52. ^ Edwin M. Kilbourne "Tryptophan Produced by Showa Denko and Ecsinophilia-Myalgia Syndrom," Journal of Rheumatology Supplement 23, no.46 (October 1996): 81-92.

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[edit] Suggested Reading

Mendel in the Kitchen, by Nina Fedoroff and Nancy Marie Brown

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