Genetically modified food

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Genetically Modified (GM) foods are produced from genetically modified organisms (GMO) which have had their genome altered through genetic engineering techniques. The general principle of producing a GMO is to insert DNA that has been taken from another organism and modified in the laboratory into an organism's genome to produce both new and useful traits or phenotypes. GM Foods have been available since the 1990s, with the principal ones being derived from plants; soybean, maize, canola and cotton seed oil.[1]


Commercial crops

Genetically Modified Plants are grown commercially in over 20 countries and on 6 continents.[2] In 2006, about 102 million Hectares were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola.[2]

Crops Under Development

The following GM crops are in development.

Abundance of GM crops

Between 1996 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% were in the United States.

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.[12] 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% from the previous season). Indian national average cotton yields have been boosted to close 50% above the long term average yield during this period. 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.[13][14]

Four countries represent 99% of total GM surface in 2001: United States (68%), Argentina (22%), Canada (6%) and China (3%). It is estimated that 70% of products on U.S. grocery shelves include GM-derived ingredients. 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" that financially benefit the producers, yet have only indirect environmental and marginal cost benefits to consumers.

In the US, by 2006 89% of the planted area of soybeans, 83% of cotton, and 61% 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 thuringiensus 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] The Grocery Manufacturers of America estimate that 75% of all processed foods in the U.S. contain a GM ingredient.

Future developments

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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. See also: GM food controversy

Safety testing

In the USA regulation of a genetically modified food is determined by the objective characteristics of the food and the intended use of the food, irrespective of the way it was developed. FDA policy states that a formal pre-market review by the FDA is to be taken when the objective characteristics of any substance added to the food raises issues of safety[16]

Prior to marketing a new GM food product, manufacturers are required to submit documentation to the FDA to demonstrate its safety and then await approval before selling it to consumers[17]

The context for assessing safety of novel foods is the fact that existing foods often contain toxic components but are still able to be consumed safely. For instance, potatoes and tomatoes can contain toxic levels of solanine and alpha-tomatine alkaloids respectively[18], and this situation is recognised in the concept of "Substantial Equivalence" that was developed by the OECD in 1993 as a criterion for identifying whether a novel food is at least as safe as the equivalent existing food. The US FDA takes a safety assessment approach that is consistent with this OECD concept in their regulation of novel foods (including those made by recombinant DNA methods). This policy is outlined in an FDA statement.[19]

Critics of GM food believe this regulatory model fails to sufficiently protect consumers and claim that the FDA is subject to pressure and influence by industry. One concern voiced is that a novel crop may have unintended changes created during the insertion of new genetic material. On the other hand, 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.[20][21]

Safety assurance and benefits

By 2006, near to 150 scientific publications had reported on the nutritional value of animals feeds (and food) derived from genetically modified crops as compared to their conventional counterparts. These studies also followed the fates of DNA and novel proteins after ingestion by animals, and more recently, provided comprehensive fingerprinting of protein profiles (which is usually called a proteomics approach[22] ) or comprehensive fingerprinting of metabolites (known as a metabolomics approach[23]) where GM crops compared to their non-GM counterparts.

Scientific reviews of this research[24][25] have concentrated so far on the first generation of genetically modified plants, with no intended gross changes in composition. These reviews find that with the first generation of genetically modified crops, there are no significant differences in feed or nutritional value as compared to nutritional performance of the corresponding conventional crop, and that no residues of recombinant DNA or novel proteins are found in any organ or tissue sample obtained from animals fed modified materials.

Comprehensive chemical fingerprinting of GM potatoes in comparison with conventional potato varieties has shown that, apart from the intended changes in food composition, the GM potatoes appeared to be substantially equivalent to traditional cultivars.[26] Other detailed comparisons of detailed protein profiles of both GM and conventional potatoes[27] detected a great deal of variation in protein profiles of different conventonally potato varieties, but found considerably fewer differences in protein profile due to insertion of a new trait by genetic engineering.

Mycotoxins are chemicals made by molds that are detrimental to human health. Many different mycotoxins are produced by various fungi such as Aspergillus or Fusarium species that grow on plants. Some of these chemicals cause liver damage, or cause cancer. In the case of the chemical called fumonisin, which is mycotoxin produced by certain Fusarium fungal species that are natural colonizers of maize plants, the fungal toxin is known to cause (i) severe human birth defects when pregnant women ingest food such as tortillas made from moldy maize, and (ii) cancer in adults when either men or women drink maize based alcoholic beverages fermented from mouldy maize. These food safety problems are serious health issues in regions where maize is a staple food in Central America, South Africa and China.

Fungal growth on maize is promoted by moisture, climatic factors, and most notably, insect predation. Several reports demonstrate that insect protected GM maize can have lower mycotoxin levels due to reduced insect damage to the crop. World-wide trade losses from mycotoxin presence in maize are hundreds of millions $US annually, with the United States, China, and Argentina suffering the greatest losses. The reduction of mycotoxins provided by Bt corn has been estimated to provide the United States alone a total benefit of $23 million annually.[28]

GM crops have shown to contribute to significantly reduced greenhouse gas emissions from agricultural practices. This reduction results from decreased fuel use, about 1.8 billion liters in the past nine years, and additional soil carbon sequestration because of reduced ploughing or improved conservation tillage associated with biotech crops. In 2004, this reduction was equivalent to eliminating more than 10 billion kg of carbon dioxide from the atmosphere. GM cotton has greatly reduced synthetic pesticide use in the US, Australia and India.[29]


Intellectual Property

Monsanto Canada Inc. v. Schmeiser

Main article: Monsanto Canada Inc. v. Schmeiser

Enforcement of Patents on genetically modified plants is often contentious, especially because of the occurrence of Gene flow . In 1998, 95-98% 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.[30] 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.[31]

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.[30][31] 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."[32]

Policy 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, not production, so people should not be offered food that may carry some degree of risk.

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.[33] 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 the Polymerase Chain Reaction method 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.[34] 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".[35] More recent attempts to replicate the original studies have concluded that genetically modified corn is absent from southern Mexico in 2003 and 2004 [9] Also in dispute is the impact on biodiversity of the introgression of transgenes into wild populations [10]. 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 breeding is a form of genetic engineering,[36] (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.[37]

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.

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 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 genera 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.

Economic and political effects

  • Many 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 excessive control over the production chain of crops and food, and over the farmers that use their products, as well.
  • Many proponents of 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 [11]. A few genetic engineering licenses allow farmers in less economically developed countries to save seeds for next year's planting.
  • In August 2002, Zambia cut off the flow of Genetically Modified Food (mostly maize) from UN's World Food Programme. Although there were claims that this left a famine-stricken population without food aid, the U.N. program succeeded in replacing the rejected grain with other sources, including some foods purchased locally with European cash donations. In rejecting the maize, Zambians cited the "Precautionary Principle" and also the desire to protect future possibilities of grain exports to Europe. [citation needed]
  • In December 2005 the Zambian government changed its mind in the face of further famine and allowed the importation of GM maize. [12]. 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." [13] [14]
  • In April 2004 Hugo Chávez announced a total ban on genetically modified seeds in Venezuela. [15]
  • 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. [16]
  • 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.[38] The U.S. government has since declared the rice safe for human consumption, and exports to some countries have since resumed.

See also

References

  1. ^ 2002 ISAAA News Release: Report Shows GM Crops Generating Global Economic, Environmental and Social Benefits
  2. ^ a b International Service for the Acquisition of Agri-biotech Applications (ISAAA), Global Status of Commercialized Biotech/GM Crops: 2006 ISAAA Briefs 35-2006[1]
  3. ^ Nuffield Council on Bioethics press release: GM crops and EU laws: G8 leaders urged to improve choice for African farmers, June 29, 2005
  4. ^ Grand Challenges in Global Health initiative, Bill & Melinda Gates Foundation, 2003 Grand Challenge #9: Create a full range of optimal, bioavailable nutrients in a single staple plant species
  5. ^ Yu et al, Seed-specific expression of the lysine-rich protein gene sb401 significantly increases both lysine and total protein content in maize seeds. Food Nutr Bull. 2005 26:427-31.
  6. ^ Oh SJ, Song SI, Kim YS, Jang HJ, Kim SY, Kim M, Kim YK, Nahm BH, Kim JK. Arabidopsis CBF3/DREB1A and ABF3 in transgenic rice increased tolerance to abiotic stress without stunting growth. Plant Physiol. 2005 May;138(1):341-51. Epub 2005 Apr 15.
  7. ^ Kasuga M, Miura S, Shinozaki K, Ya K. A combination of the Arabidopsis DREB1A gene and stress-inducible rd29A promoter improved drought- and low-temperature stress tolerance in tobacco by gene transfer. Plant Cell Physiol. 2004 Mar;45(3):346-50.
  8. ^ Pellegrineschi A, Reynolds M, Pacheco M, Brito RM, Almeraya R, Yamaguchi-Shinozaki K, Hoisington D. Stress-induced expression in wheat of the Arabidopsis thaliana DREB1A gene delays water stress symptoms under greenhouse conditions.Genome. 2004 Jun;47(3):493-500.
  9. ^ Zhang HX, Hodson JN, Williams JP, Blumwald E. Engineering salt-tolerant Brassica plants: characterization of yield and seed oil quality in transgenic plants with increased vacuolar sodium accumulation. Proc Natl Acad Sci U S A. 2001 Oct 23;98(22):12832-6. Epub 2001 Oct 16.
  10. ^ May 1, 2006 – A Breakthrough For Second Leading Killer of Children Under Five – A Medical Food for Acute Diarrhea
  11. ^ Zavaleta et al Efficacy of rice-based oral rehydration solution containing recombinant human lactoferrin and lysozyme in Peruvian children with acute diarrhea. Pediatr Gastroenterol Nutr. 2007 44:258-64
  12. ^ [2]
  13. ^ Economic Impact of Genetically Modified Cotton in India
  14. ^ Comparing the Performance of Official and Unofficial Genetically Modified Cotton in India
  15. ^ Adoption of Genetically Engineered Crops in the U.S. USDA ERS July 14, 2006
  16. ^ [http://www.cfsan.fda.gov/~acrobat/fr920529.pdf Foods Derived from New Plant Varieties. Federal Register 57 104, 22984, May 29 1992], FDA, U.S. Department of Agriculture
  17. ^ United States Food Safety System, FDA, U.S. Department of Agriculture
  18. ^ Agbios commentary on substantial equivalence
  19. ^ FDA, "Statement of Policy: Foods Derived from New Plant Varieties", (GMO Policy), Federal Register, Vol. 57, No. 104 (1992), p. 22991
  20. ^ Proteomic profiling and unintended effects in genetically modified crops, Sirpa O. Kärenlampi and Satu J. Lehesranta 2006
  21. ^ 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
  22. ^ [3]
  23. ^ [4]
  24. ^ [5]
  25. ^ [6]
  26. ^ [7]
  27. ^ [8]
  28. ^ Discussed fully by Felicia Wu, University of Pittsburgh, Mycotoxin Reduction in Bt Corn: Potential Economic, Health, and Regulatory Impacts in Transgenic Research (2006) 15:277–289
  29. ^ PG Economics
  30. ^ a b Munzer, Stephen R. (2006). "Plants, Torts, and Intellecutal Property". Oxford University Press: 1–30. {{cite journal}}: Cite journal requires |journal= (help)
  31. ^ a b Federal court of Canada. Monsanto Canada Inc. v. Schmeiser Date: 20010329 Docket: T-1593-98 Retrieved 26-Mar-2006.
  32. ^ Schubert, Robert: "Schmeiser Wants to Take It to The Supreme Court", CropChoice News, Sept. 9, 2002
  33. ^ Quist D and Chapela IH "Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico". Nature. 414 (6863): 541–543. 2001. doi:10.1038/35107068.
  34. ^ 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.
  35. ^ "Biodiversity (Communications arising): Suspect evidence of transgenic contamination". Nature. 416 (6881): 600–601. 2002. doi:10.1038/nature738.
  36. ^ Fedoroff NV "Prehistoric GM corn". Science. 302: 1158–1159. 2003.
  37. ^ Schubert D "Regulatory regimes for transgenic crops". Nat Biotechnol. 23: 785–787. 2005.
  38. ^ http://www.npr.org/templates/story/story.php?storyId=6734070

External links

Wikibooks has a book on the topic of: Genes, Technology and Policy

Suggested Reading

  • Jeffry M. Smith Seeds of Deception: Exposing Industry and Government Lies About the Safety of the Genetically Engineered Foods You're Eating, Yes! Books, 2003, ISBN: 0972966587
  • McHughen, A. Pandora's Picnic Basket : The Potential and Hazards of Genetically Modified Foods, Oxford University Press, 2000
  • Tokar, B.(ed.) Redesigning Life? Zed Books, 2001.
  • Let Them Eat Precaution. How Politics Is Undermining the Genetic Revolution in Agriculture. By Byrne, J., Conko, G., Entine, J., Gilland, T., Hoban, T. H., Moore, P., Natsios, A. S, Newell-McGloughlin, M., Paarlberg, R. L., Prakash, C. S., Tucker Foreman, C., Edited by Jon Entine AEI Press (Washington) 2006. Facets of the GM crop debate not covered by antagonists to the technology.
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