Genetically modified food

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Kenyans examining insect-resistant transgenic Bt corn.
Kenyans examining insect-resistant transgenic Bt corn.

Genetically modified (GM) foods are foods made from genetically modified organisms (GMO) that have had their DNA altered through genetic engineering. GM foods were first put on the market in the early 1990s. The most common modified foods are derived from plants: soybean, corn, canola, and cotton seed oil.[1][2]

Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation.

Contents

[edit] Overview

The process of producing a GMO used for GM Foods may involve taking DNA from one organism, modifying it in a laboratory, and then inserting it into the target organism's genome to produce new and useful genotypes or phenotypes. Such GMOs are generally referred to as transgenics. Other methods of producing a GMO include increasing or decreasing the number of copies of a gene already present in the target organism, silencing or removing a particular gene or modifying the position of a gene within the genome.

[edit] Development

The first commercially grown genetically modified whole food crop was the Flavr Savr tomato, which was made more resistant to rotting by Californian company Calgene.[3] Calgene was allowed to release the tomatoes into the market in 1994 without any special labeling.[4] It was welcomed by consumers that purchased the fruit at two to five times the price of regular tomatoes. However, production problems[3] 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.[5] The labeling and pricing were designed as a marketing experiment, which proved, at the time, that European consumers would accept genetically engineered foods.

The attitude toward GM foods would be drastically changed after outbreaks of Mad Cow Disease weakened consumer trust in government regulators, and protesters rallied against the introduction of Monsanto's "Roundup-Ready" soybeans.[citation needed] The next GM crops included insect-resistant cotton[6][7] and herbicide-tolerant soybeans[8] both of which were commercially released in 1996. GM crops have been widely adopted in the United States. They have also been extensively planted in several other countries (Argentina, Brazil, South Africa, India, and China) where the agriculture is a major part of the total economy. Other GM crops include insect-resistant maize and herbicide-tolerant maize, cotton, and rapeseed varieties.

[edit] GM Foods currently

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

Food Properties of the genetically modified variety Trade name and the company which produced initial version Specific genetic modification Percent the genetically modified version occupies of the given foods' agriculture in USA Percent this GMF takes up of agriculture compared to its non-GMF version, globally
Soybeans Resistant to herbicides Roundup Ready, Monsanto Herbicide resistant gene taken from bacteria inserted into soy bean TBA TBA
Corn Resistance to certain pesticides (tolerating crop spray - this way a farmer can use amounts of pesticides which would normally kill the plant, without harming it) TBA New gene added/transferred into plant genome TBA TBA
Cotton Pest-resistant cotton TBA New gene added/transferred into plant genome TBA TBA
Tomatoes Variety that does not rot (degrade) as fast - the genetically modified tomatoes do not produce a substance that normally causes tomatoes to rot. E.g. FlavrSavr First genetically modified tomatoes contained genes that made them resistant to antibiotics. After concern from doctors and the medical community, tomatoes are now genetically modified in an alternative way TBA TBA
Rapeseed plants Resistance to certain pesticides (tolerating crop spray) TBA New gene added/transferred into plant genome TBA TBA
Sugar cane Resistance to certain pesticides (tolerating crop spray) TBA 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 Insect-killing gene added to the plant. The gene comes from the bacteria Bacillus thuringiensis. 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

[edit] Potatoes

[edit] Abundance of GM crops

Between 1995 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.)[9] 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 2006/7 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 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. Economic and environmental benefits of GM cotton in India to the individual farmer have been documented.[10][11]

In 2003, countries that grew 99 percent of the global transgenic crops were the United States (63 percent), Argentina (21 percent), Canada (6 percent), Brazil (4 percent), China (4 percent), and South Africa (1 percent).[12] The Grocery Manufacturers of America estimate that 75 percent of all processed foods in the U.S. contain a GM ingredient [13] . 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 percent of cotton, and 61 percent maize was 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.[14]

However, several studies have found that genetically modified varieties of plants do not produce higher yields than normal plants.[15]

[edit] Coexistence and traceability

In many parts of the world such as the European Union, Japan, Malaysia and Australia consumers demand labelling so they can exercise choice between foods that have genetically modified, conventional or more natural organic origins.[16][17] This requires a labelling system as well as the reliable separation of GM and non-GM organisms at production level and throughout the whole processing chain.[16][17]

Research has demonstrated, that coexistence of GM crops can be realised by several agricultural measures, such as isolation distances or biological containment strategies.

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 labelling 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.

The GM food controversy is a dispute over the advantages and disadvantages of genetically modified food crops. See Genetically modified food controversies.

[edit] Debate around the world

Some 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.[18][19]

Others oppose genetic engineering on the grounds that genetic modifications might have unforeseen consequences, both in the initially modified organisms and their environments. For example, certain strains of maize have been developed that are toxic to plant eating insects (see Bt corn). It has been alleged those strains cross-pollinated with other varieties of wild and domestic maize and passed on these genes with a putative impact on Maize biodiversity.[20] Subsequent to the publication of these results, several scientists pointed out that the conclusions were based on experiments with design flaws. It is well known that the results from polymerase chain reaction (PCR) methods of analysing DNA can often be confounded by sample contamination and experimental artifacts. Appropriate controls can be included in experiments to eliminate these as a possible explanation of the results - however these controls were not included in the methods used by Quist and Chapela.[21] After this criticism Nature, the scientific journal where this data was originally published concluded that "the evidence available is not sufficient to justify the publication of the original paper".[22] More recent attempts to replicate the original studies have concluded that genetically modified corn is absent from southern Mexico in 2003 and 2004 [23]. Also in dispute is the impact on biodiversity of the introgression of transgenes into wild populations [6]. Unless a transgene offers a massive selective advantage in a wild population, a transgene that enters such a population will be maintained at a low gene frequency. In such situations it can be argued that such an introgression actually increases biodiversity rather than lowers it.

Activists opposed to genetic engineering say that with current recombinant technology there is no way to ensure that genetically modified organisms will remain under control, and the use of this technology outside secure laboratory environments carries potentially unacceptable risks to both farmed and wild ecosystems.

Potential impact on biodiversity may occur if herbicide-tolerant crops are sprayed with herbicide to the extent that no wild plants ('weeds') are able to survive. Plants toxic to insects may mean insect-free crops. This could result in declines in other wildlife (e.g. birds) which feed on weed seeds and/or insects for food resources. The recent (2003) farm scale studies in the UK found this to be the case with GM sugar beet and GM rapeseed, but not with GM maize (though in the last instance, the non-GM comparison maize crop had also been treated with environmentally-damaging pesticides subsequently (2004) withdrawn from use in the EU).

Although some scientists have claimed that selective breeding is a form of genetic engineering,[24] (e.g., maize was modified from teosinte, dogs have evolved with human intervention over the course of tens of thousands of years from wolves), others assert that modern transgenesis-based genetic engineering is capable of delivering changes faster than, and sometimes of different types from, traditional breeding methods.[25]

Proponents of current genetic techniques as applied to food plants cite the benefits that the technology can have, for example, in the harsh agricultural conditions of Africa. They say that with modifications, existing crops would be able to thrive under the relatively hostile conditions providing much needed food to their people. Proponents also cite golden rice and golden rice 2, genetically engineered rice varieties (still under development) that contain elevated vitamin A levels. There is hope that this rice may alleviate vitamin A deficiency that contributes to the death of millions and permanent blindness of 500,000 annually.[26]

Proponents say that genetically-engineered crops are not significantly different from those modified by nature or humans in the past, and are as safe or even safer than such methods. There is gene transfer between unicellular eukaryotes and prokaryotes. There have been no known genetic catastrophes as a result of this. They argue that animal husbandry, Food Irradiation and crop breeding are also forms of genetic engineering that use artificial selection instead of modern genetic modification techniques. It is politics, they argue, not economics or science, that causes their work to be closely investigated, and for different standards to apply to it than those applied to other forms of agricultural technology.

Proponents also note that species or genetic barriers have been crossed in nature in the past. An oft-cited example is today's modern red wheat variety, which is the result of two natural crossings made long ago. It is made up of three groups of seven chromosomes. Each of those three groups came from a different wild wheat grass. First, a cross between two of the grasses occurred, creating the durum wheats, which were the commercial grains of the first civilizations up through the Roman Republic. Then a cross occurred between that 14-chromosome durum wheat and another wild grass to create what became modern red wheat at the time of the Roman Empire.

[edit] Economic and political effects

  • Some opponents of current genetic engineering believe the increasing use of GM in major crops has caused a power shift in agriculture towards Biotechnology companies, which are gaining more control over the production chain of crops and food, and over the farmers that use their products, as well.[citation needed]
  • Many proponents of some current genetic engineering techniques believe it will lower pesticide usage and has brought higher yields and profitability to many farmers, including those in developing nations [7]. 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. [8]. 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." [9] [10]
  • In April 2004 Hugo Chávez announced a total ban on genetically modified seeds in Venezuela. [11]
  • 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. [12]
  • 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.[27] The U.S. government has since declared the rice safe for human consumption, and exports to some countries have since resumed in 1983 but in the past years more crops have started to cross-pollinate which leaves a problem that is yet to be solved.[citation needed]

[edit] Intellectual property

Enforcement of patents on genetically modified plants is often contentious, especially because of the occurrence 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.[28] 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.[29]

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.[28][29] 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.

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."[30] 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, metabolically engineered fish that mature more quickly, fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties. 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.[31][32]

[edit] See also

[edit] References

  1. ^ 2002 ISAAA News Release: Report Shows GM Crops Generating Global Economic, Environmental and Social Benefits
  2. ^ Genetically Engineered Crops
  3. ^ a b Martineau, Belinda (2001). First Fruit: The Creation of the Flavr Savr Tomato and the Birth of Biotech Foods. McGraw-Hill, 269. ISBN 978-0071360562. 
  4. ^ FDA Consumer Letter (September 1994): First Biotech Tomato Marketed
  5. ^ GEO-PIE Project - Cornell University[1]
  6. ^ A Cotton Conundrum, Perspectives on Line, North Carolina State University [2]
  7. ^ Cotton Update 2006, Western Australian Dept. of Agriculture and Food, page 6[3]
  8. ^ History of Monsanto at Monsanto.com[4]
  9. ^ Need a more specific citation for this data than the ISAAA homepage.
  10. ^ Economic Impact of Genetically Modified Cotton in India
  11. ^ Comparing the Performance of Official and Unofficial Genetically Modified Cotton in India
  12. ^ Genetically Modified Foods and Organisms
  13. ^ Genetic Engineering: The Future of Foods?
  14. ^ Adoption of Genetically Engineered Crops in the U.S. USDA ERS July 14, 2006
  15. ^ UK Organic Group Exposes Myth that Genetically Engineered Crops Have Higher Yields
  16. ^ a b northwestern.edu 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 politicisation of GMOs is not merely a question of labelling as information, but unlabelled GM products as catalysts in the "globalization backlash."
  17. ^ a b CBC Identifying genetically modified products. Quote: Yet as seen in this report from CBC's Marketplace, no such labelling law exists in Canada despite numerous surveys indicating up to 90 per cent of Canadians want mandatory labelling of GM food. Canada's leading national consumer group does not support mandatory labelling.
  18. ^ Lappe FM, Collins J, Rosset P, and Esparza L (1998) World Hunger: Twelve Myths. Grove Press, 224. ISBN 978-0802135919. 
  19. ^ Boucher D (1999) The Paradox of Plenty: Hunger in a Bountiful World. Food First, 342. ISBN 978-0935028713. 
  20. ^ Quist D and Chapela IH Quist, David (2001). "Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico". Nature 414 (6863): 541-543. doi:10.1038/35107068. 
  21. ^ Christou, Paul (2002). "No Credible Scientific Evidence is Presented to Support Claims that Transgenic DNA was Introgressed into Traditional Maize Landraces in Oaxaca, Mexico". Transgenic Research 11 (1): 3-5. doi:10.1023/A:1013903300469. 
  22. ^ Metz, Matthew (2002). "Biodiversity (Communications arising): Suspect evidence of transgenic contamination". Nature 416 (6881): 600-601. doi:10.1038/nature738. 
  23. ^ Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004), S. Ortiz-García et al 2005 PNAS 102 p12338-12343 [5]
  24. ^ Fedoroff, Nina V. "Prehistoric GM corn" (2003). Science 302: 1158-1159. 
  25. ^ Schubert D "Regulatory regimes for transgenic crops" (2005). Nat Biotechnol 23: 785-787. 
  26. ^ Halford NCordell, Halford. N (2003). Genetically Modified Crops. Imperial College Press. ISBN 1-86094-353-5. 
  27. ^ Agriculture Department Probes Rice Flap : NPR
  28. ^ a b Munzer, Stephen R. (2006). "Plants, Torts, and Intellectual Property". 1-30. Oxford University Press
  29. ^ a b Federal court of Canada. Monsanto Canada Inc. v. Schmeiser Date: 20010329 Docket: T-1593-98 Retrieved 26-Mar-2006.
  30. ^ Schubert, Robert: "Schmeiser Wants to Take It to The Supreme Court", CropChoice News, Sept. 9, 2002
  31. ^ Proteomic profiling and unintended effects in genetically modified crops, Sirpa O. Kärenlampi and Satu J. Lehesranta 2006
  32. ^ 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

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