Bronze-level articleGenetically modified food

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Genetically modified food or, more correctly, genetically engineered food or transgenic food[1] is any food derived from organisms which had their genomes modified using the technique of DNA recombination.[wp] In this technique, genetic material is isolated from one organism and directly introduced into another. There is no requirement for the source and target organisms to be sexually compatible, and the transfer of genes can be highly specific, introducing only a single desired trait. This is unlike conventional breeding, which requires sexual compatibility and results in offspring with a mixture of traits from both parents.

The abbreviations GM (genetically modified) and GMO (genetically modified organisms) are commonly used. GMO can also include organisms genetically modified for purposes other than food, such as laboratory animals used in clinical research or non-food crops, such as cotton and poplars.

So far, all genetically modified foods on the market are plants. Genetically modified fish[wp] such as salmon have also been developed, but food regulators such as the USA's Food and Drug Administration have not yet approved these for farming and public consumption.

Opponents of GM food claim that its production has negative environmental impacts, that its consumption has adverse health effects, and that the companies that profit from it, notably the Monsanto corporation, are plotting to control the world food supply or achieve some other evil. This has resulted in intense public debate, even though the scientific consensus says very clearly that GMO food is safe [2] and the anti-GMO position is represented in the academic community by a tiny minority of researchers, many of them with ideological and financial conflicts of interest.[3]

Proponents claim that GM technology has been the subject of a manufactroversy and accuse opponents of spreading misinformation through the media.[4][5][6]

The most controversial instance of opposition to GM food is probably the case of Zambia. In 2002, the Zambian government opted to let its people starve in the midst of a region-wide crop failure by turning down a vast quantity of food aid in the form of GM corn, rather than feed them "GM poison".[7]

Contents

[edit] Pros and cons

Since DNA recombination is a very powerful technique which allows for almost arbitrary modifications to be introduced into the genome, GM food can have a variety of traits which do not occur in nature and are impossible to obtain using others methods of breeding. It is a way to short-circuit the millions of years of evolution and artificial selection which would be required for the desirable traits to arise spontaneously. This includes resistance to pests, viruses and herbicides, drought tolerance and improved nutritional value.

On the other hand, the newly introduced traits might disrupt the ecosystem surrounding a GM crop field, particularly when GM crops interbreed with wild relatives. There exists technology to prevent interbreeding, but it is not used due to its negative public perception.[8] Most GM traits are also covered by patents, which means that cultivating a GM crop requires the payment of license fees to the company which commercialized the given trait. This has good as well as bad consequences: the bad ones are of course that only one company has a monopoly on the given traits, which increases prices and slows down adoption. The good consequence is that the company can demand additional environmental requirements for crop planting, such as mandating weed and insect refuges, which slow down or prevent the onset of resistance to GM traits.

[edit] Common GM traits

The most common GM traits found in commercial crops focus on increasing yields by conferring immunity to pests, weeds and diseases. These traits translate into easily quantifiable financial gains for the farmer, so they were the first to be commercialized. The majority of GM crops have one or more of the following traits:

  • Herbicide tolerance (HT). This type of trait confers immunity to a herbicide, typically glyphosate (also known as Roundup). Spraying with this herbicide kills the weeds without affecting the crop. This allows the farmer to easily avoid tillage. Tillage is normally done to control weeds, but accelerates soil erosion. HT crops usually require more herbicides than traditional ones, but the broad spectrum herbicides used on HT crops are typically less toxic than traditional selective herbicides, leading to a net reduction of the environmental footprint. Corn[9], canola, soy, and sugar beets[10] are examples of common HT crops.
  • Bt toxin production. Bt toxins are proteins produced by the soil bacterium Bacillus thuringens which are lethal to some species of insect pests, primarily moths and beetles. Bt extract is often used as an insecticide in organic farming. When an insect attempts to feed off a plant that produces a Bt toxin, it quickly dies. Bt crops require significantly less insecticides than their traditional counterparts. Note that there are now several different Bt toxin strains, each of which is lethal to a slightly different segment of the insect population and each of which has its own tracking number assigned to it by the EPA.[11] Corn and cotton are examples of common Bt crops.
  • Virus resistance. By introducing genes coding for viral coat proteins, plants can be made resistant to viruses. The best known example is the Rainbow variety of papaya, which is resistant to the papaya ringspot virus and is credited with saving the papaya farming industry in Hawaii.[12] Unfortunately, the specific variety chosen to receive the ringspot virus resistance transgene turned out to be vulnerable to blackspot fungus, so now a second round of genetic modification is trying to breed in blackspot fungus resistance.

[edit] GM traits not yet in use

There are also many other possible traits in the research stage or awaiting regulatory approval.

  • Increased intrinsic yield. There is an ongoing research project called C4 Rice, which aims to create rice which uses the more efficient C4 photosynthesis pathway from corn, rather than the C3 photosynthesis native to rice.[13] If it ever proves successful, it may open the door to creating C4 wheat, C4 potatoes, C4 sugar beets, etc..
  • Nitrogen fixation. There is a project to achieve symbiosis between nitrogen-fixing bacteria and cereals, a feature now restricted to legumes, which would obviate or significantly reduce the need for artificial fertilizer in their cultivation.[14]
  • Disease resistance. This ranges from blight-resistant potatoes[15] to bananas resistant to fusarium wilt.[16]
  • Biofortified food has increased nutritional value or contains essential nutrients not present in traditional varieties. The best known example is Golden Rice, a humanitarian project to develop rice containing vitamin A (beta-carotene) in order to prevent vitamin A deficiency induced blindness in the developing countries.[17] Tomatoes containing anthocyanin (the antioxidant that makes blueberries blue) are also under development.[18]
  • Improved handling characteristics. This includes the now discontinued Flavr Savr tomato with delayed ripening, the nonbrowning Arctic Apple[19], and Simplot's harder-to-bruise potato.[20]
  • Improved digestion. The "Enviropig"[21] was engineered to more efficiently digest plant phosphorus, eliminating the need to feed it phosphorus supplements.

[edit] Controversy over GM food

Several concerns have been raised over GM foods:

[edit] Lack of independent testing

Concern exists over lack of independent testing of GM foods. FDA regulations require new GM strains to be tested for things like allergen potential and toxicity, but these tests are allowed to be conducted by the manufacturers (with FDA oversight).[more detail please] However, there are no regulations requiring the testing of new crop strains produced by non-GM means, such as cross-breeding or induced mutation; thus, non-GM varieties are not tested at all. So even manufacturer testing is sometimes a substantial improvement.

Note that many manufacturers do not run the studies themselves, but contract them out to research institutes; and the manufacturer-run studies are examined by the FDA during the approval process, making it rather difficult to falsify results.[citation needed]

[edit] Food allergies

The rise in food allergies correlates to the rise of GM foods. A 2013 article in that bastion of scientific rigor, Elle magazine, claimed that the author's apparent allergy to corn wouldn't have happened if our corn wasn't genetically modified.[22]

All that can be said is correlation does not equal causation. The rise in allergies is a common phenomenon in developed countries, even though the popularity of GM food varies wildly between them. Furthermore, new proteins introduced by genetic modification are required to have short digestion times in order to be found fit for human consumption, precisely because long-digestion proteins are potential allergens. Starlink corn is a famous example of a GM crop that was found unfit for human consumption (long before it was brought to market as cattle feed) on this basis.

[edit] Environmental impact of GM herbicide resistance

What is the impact on the environment where GM resistance leads to increased use of herbicides? So far there is very little data suggesting a major increase in herbicide use, and this completely ignores how glyphosate is far less toxic than many alternative herbicides (such as atrazine) - meaning that increases in the mass of herbicide used do not always translate to an increase in environmental impact. Sustained glyphosate use and poor management practices have led to some weeds becoming resistant to the herbicide.[23] Proper weed management practices and careful use of selective herbicides can help mitigate this resistance.

The number of reported new cases of herbicide-resistant weeds has actually slightly decreased after the introduction of GM crops. Out of the 24 known glyphosate-resistant species, 13 were actually first documented in non-GM crops. As such, superweeds are a problem related to herbicide use and not directly to GM crop use.[24]

[edit] Lateral gene transfer

What might happen if modified genes transfer laterally to other organisms? For example, herbicide resistance could transfer to related weedy species, producing herbicide resistant weeds - obviously an undesirable outcome. Occurrence of this gene flow has been confirmed in field studies,[25] but so far it's uncertain whether this is a serious concern or not.[Who?] It should be noted that herbicide resistance is not unique to GM crops (for instance, imidazolinone-resistant canola was obtained using radiation breeding), nor does herbicide resistance in weeds require gene flow to occur.

There are technologies available to prevent the spread of transgenes in the environment by making the second-generation seed of GM plants sterile, but they are not used due to public opposition (see "Terminator seed technology" below).

[edit] Legal implications of cross-pollination

What are the legal implications of cross-pollination between GM crops and non-GM crops planted on other farms nearby? While activists commonly claim that biotech companies (like Monsanto) will sue farmers for accidental contamination via cross-pollination, such lawsuits have not happened. In 2012, a group of organic farmers preemptively sued Monsanto for this very reason, but their case was thrown out when they were unable to present any evidence that supported their claims.[26] It is unlikely that any judge would rule in favor of Monsanto in such a case, because the farmer would not obtain any undue benefit from the patented seeds.

Percy Schmeiser's case is often used as an example by activists - but the court found that he intentionally selected for GM traits in canola pollinated from a neighboring field by spraying his own field with glyphosate, which killed off all of his plants but left the pollination-planted ones intact, and then used the seed on his farm, planting a total of approximately 1,030 acres with the seed. Schmeiser attempted to claim that he was innocent and that the glyphosate-resistant crops appeared on his fields via pollination or from a passing truck's spillage, but the judge pointed out that all 1,030 acres were planted with glyphosate-resistant canola at a purity of 95-98%, far beyond the 0.5-2% typically seen from accidental contamination. Furthermore, the fact that Schmeiser intentionally sprayed glyphosate on his crops betrayed his knowledge of the seed, since glyphosate will kill any non-resistant plants. Monsanto won the lawsuit, but Schmeiser mounted a massive misinformation campaign online, which has led to a great many people being unaware of the true facts on this case.[27]

GM traits are usually patented. While this draws a lot of criticism, this situation is in fact not any different from conventional breeding, where novel traits are also patentable.[28] "Plant patents" have been protected by U.S. law since 1930. Several patents on first-generation GM traits are due to run out in the near future; the patent for first-generation RoundUp Ready soybean seeds, for example, will expire in 2015.

[edit] Health implications of cross-pollination

It's not just the legal implications of cross-pollination some are concerned with. The health implications of cross-pollination between GM crops and non-GM crops planted on other farms nearby has also garnered some attention.

Starlink corn, a Bt corn variety using a different gene than Monsanto's, was declared unfit for human consumption because one of the introduced proteins (Cry9C) had a long digestion time and was thus a potential allergen. Starlink corn was, however, deemed fit for animal consumption, and was grown as cattle feed. Soon thereafter, Cry9C proteins were found in foodstuffs that were deemed fit for human consumption.[29] Pollen containing the Bt genes had apparently hopped the fence into neighboring cornfields. While no cases of allergic reaction to Cry9C have been confirmed,[30] this raises the spectre of other GM traits escaping isolation.

[edit] Lack of biodiversity


When a GM crop is first introduced, the seeds are usually derived from a single strain. If this crop becomes immensely popular, you'll end up with multiple farmers planting one and only one strain of the crop, leaving all of these new crops vulnerable to disease. This happened with the Rainbow papaya: the strain chosen to receive the transgene for ringspot-virus resistance turned out to be vulnerable to the blackspot fungus. The problem can be avoided by breeding the GM trait into several varieties using conventional methods.

GM crops are not the only crops lacking biodiversity, nor is lack of biodiversity a new concern. The Great Irish Potato Famine occurred largely because Irish farmers planted only one strain of potatoes; when the Potato Blight struck, it struck 'em all. McDonald's has long been criticized for its reliance on the Russet Burbank strain of potatoes for its French fries, to the exclusion of other strains.

[edit] "Terminator seed" technology

A common myth is that the crops use "terminator seed" technology (technical name Genetic Use Restriction Technology, GURT) which causes the crops to yield sterile seeds. However, while testing has been conducted on GURT, there is actually a moratorium on its commercial use due to public opposition.[31] Monsanto has also pledged not to use the technology.[32]

Despite all the propaganda, GURT is actually a good thing because it stops planted GM crops from expanding into the wild - one of the few realistic concerns about GM crops. Seed that cannot be saved for replanting is nothing new. Plants grown from traditional hybrid seed, in wide use since the 1920s, do not produce true copies in the second generation due to the existence of hybrid vigor. Therefore, new seed must be bought every year from a plant breeder to keep its desirable characteristics.[33]

[edit] GMO labelling laws

As of early 2014, two U.S. states, Maine and Connecticut, have laws requiring foods containing genetically-modified crops to be labelled as such. 30 more states have similar bills pending in their legislatures.[34] The proponents of such labelling laws are mostly anti-GMO activists for whom labelling laws are but a first step.[35] The opponents assert that such laws would make "no GMOs!" labels into selling points for a gullible public (much like "all natural!" labels do today), and would give no useful information about which genetic modifications are and aren't present.

[edit] The evidence so far

So far, all evidence is overwhelmingly in favor of safety of GM foods for human consumption.[36][37] A wide variety of reputable organizations have stated that genetically modified foods are safe to eat, including the US National Academies of Sciences,[38] the American Association for the Advancement of Science,[39] the European Commission,[40] and many more. Some articles even argue that the repression of GM foods by the environmental movement is the real problem.[41] At least one high-profile environmentalist has changed his anti-GMO stance as a result of learning the actual science.[42] (Did he simply sell out to Monsanto? A lot of anti-GMO bloggers and sites at the time thought so,[43] but evidence has not been forthcoming.)

GM crops can of course be misused, and for this reason need oversight. However, after years of cultivation, there seem to be no adverse impacts associated specifically with them, and in many cases they confer significant environmental and health benefits (e.g. Bt corn contains less carcinogenic fungal toxins than regular corn, HT crops prevent soil erosion by simplifying no-till farming, and so on). The continued insistence of anti-GMO activists that the science is uncertain is simply moving the goalposts.

Additionally, anti-GMO activists use the precautionary principle argument which states that as there is negative proof of the harm of GE foods (i.e. there is no absolute, ultimate proof that GM food is safe), GMOs should be opposed.[44][45] Arguments of this nature are invalid, as any given technology cannot be proven to be safe in every possible imagined circumstance.

[edit] Pseudoscience regarding GM food

Attacks on GM food often utilize pseudoscience.

[edit] GM crops and health

The most prevalent claim is that all GMOs are harmful to health and cause a variety of illnesses: cancer,[46] autism,[47] reproductive problems, infant mortality, liver problems and many other things.[48] These claims are totally false and on the same level as vaccine hysteria. Many of these claims are spread on the internet by cranks (such as NaturalNews, Joseph Mercola, FoodBabe.com, and the Institute for Responsible Technology); more generally by groups like the non-GMO project; and by environmental groups such as Greenpeace[49] and the Sierra Club.[50]

The scientific consensus says that there are no generic health risks common for all GM food. Any possible harm can only come from a specific engineered trait. This view is shared by the World Health Organization,[51] the Food and Agriculture Organization of the United Nations, the European Food Safety Agency, the International Council for Science,[52] the U.S. National Academies of Science,[53] and almost all national scientific bodies. According to one metastudy which included 12 long-term studies and 12 multigenerational studies: "The studies reviewed present evidence to show that GM plants are nutritionally equivalent to their non-GM counterparts and can be safely used in food and feed."[54] GM traits currently on the market have been tested in animals and found safe.[citation needed]

[edit] Seed fertility

Anti-GMO activists often say that GM seeds are infertile.[55] This refers to Genetic Use Restriction Technology, dubbed "terminator seed", which renders the second generation seed of a plant infertile. (See "Terminator seed technology" above.) This would prevent the farmer from saving seed, which currently is a requirement enforced using legal means.

GURT was never commercialized and work on it was abandoned in 1999,[56] largely due to public backlash instigated by the anti-GMO campaigners. Ironically, it would solve one of the few real problems with GM crops, namely the transfer of GM traits into wild relatives. It would also enable the safe use of GM plants to produce pharmaceutically active compounds.[57]

[edit] Influence on bees

There are also claims that Bt crops are responsible for bee deaths and colony collapse disorder (CCD). This is false. Bt toxin is harmful to some Lepidoptera (butterflies / moths) and Coleoptera (beetles) which feed directly on the plant. It is not harmful to bees, which are in the order Hymenoptera. A meta-analysis of 25 studies found that there is no detectable harm to bees arising from the use of Bt crops.[58] In fact, imidacloprid, a pesticide used on corn crops, is toxic to bees; and the whole point of Bt corn crops is that they need to be sprayed with less pesticide.

[edit] Farmer suicide in India

Some anti-GMO activists also claim that Bt cotton in India ruins small farmers and drives them to suicide. Bt cotton in India is not a substantial factor in farmer suicides, which started rising 5 years before its introduction.[59] In fact, a long-term study on the economic impacts of Bt cotton in India showed that Bt cotton has increased yields, profits, and the living standards of smallholder farmers.[60]

[edit] See also

[edit] Pro-GMO

[edit] Anti-GMO

[edit] Footnotes

  1. The genomes of nearly all important crops are heavily modified with respect to their wild ancestors through the process of selective breeding and in many cases also by other techniques such as hybridization and mutation breeding, so using the term "genetically modified" specifically to label recombinant organisms is something of a misnomer.
  2. A. Nicolla, A. Manzo, F. Veronesi, D. Rosellini, An overview of the last 10 years of genetically engineered crop safety research Critical Reviews in Biotechnology, 2014, 34(1), 77-88
  3. Gilles-Eric Séralini, tied to a Big Placebo company and funded by anti-GMO organizations, is a notable example.
  4. Gorski, David More bad science in the service of anti-GMO activism Science-Based Medicine
  5. Labels for GMO Foods Are a Bad Idea Scientific American
  6. Kloor, Keith GMO Opponents Are the Climate Skeptics of the Left Slate
  7. BBC News: Zambia refuses GM 'poison'
  8. Namely, Variety GURT, which renders sterile all seed produced by the plant. Sterile seeds can't crossbreed with anything. Called "terminator seed technology" by its opponents, it attracted so much misguided outrage that it has been abandoned, as described in the Controversy section later in this article.
  9. In 2010, 16% of U.S. corn had the Bt trait, 23% had the HT trait, and 47% had both. Source: http://usda.mannlib.cornell.edu/usda/nass/Acre/2010s/2010/Acre-06-30-2010.pdf
  10. ISAAA Brief 43-2011. Executive Summary: Global Status of Commercialized Biotech/GM Crops: 2011
  11. Hayes' Handbook of Pesticide Toxicology
  12. Transgenic Virus-Resistant Papaya: The Hawaiian ‘Rainbow’ was Rapidly Adopted by Farmers and is of Major Importance in Hawaii Today, on APSnet
  13. International Rice Research Institute: C4 Rice. As of December 2012, the C4 Rice Consortium apparently hasn't yet isolated the genes responsible for C4 photosynthesis.
  14. John Innes Center: Major investment to persuade bacteria to help cereals self-fertilise
  15. BBC News: Blight-resistant GM potatoes field trial begins
  16. The Age: Disease-resistant banana plant developed
  17. http://www.goldenrice.org/
  18. Genetically-modified purple tomatoes heading for shops, BBC News, 24-Jan-2014
  19. Acrtic Apples. Since the spliced-in genes come from other apples, Okanagan Specialty Fruits proudly touts "no frankenfood here!", implying that they want to distance themselves from all those "nasty" GMO producers.
  20. Simplot's website. Like the Arctic Apple, Simplot doesn't use transgenes from other unrelated species, but instead manipulates the potato genes directly.
  21. http://www.uoguelph.ca/enviropig/
  22. The Bad Seed: The Health Risks of Genetically Modified Corn, in the Hair and Beauty section of the 24-July-2013 Elle. Rebuttal on Slate: No, You Shouldn’t Fear GMO Corn, 7-Aug-2013.
  23. Facts about Glyphosate-Resistant Weeds
  24. Where are the super weeds?
  25. Watrud, L.S. et al., Evidence for landscape-level, pollen-mediated gene flow from genetically modified creeping bentgrass with CP4 EPSPS as a marker. Proceedings of the National Academy of Sciences, October 5, 2004, vol. 101, no. 40, pp. 14533-14538.
  26. OSGATA v. Monsanto decision
  27. Federal Court (Canada) decision - Monsanto Canada Inc. v. Schmeiser
  28. swissinfo.ch: New e-licencing platform highlights patent debate - note that this article is not about GM traits, since neither of the two traits approved for cultivation in the EU belongs to Syngenta.
  29. Taco Bell Recalls Shells That Used Bioengineered Corn
  30. CDC, National Center for Environmental Health. Investigation of Human Health Effects Associated with Potential Exposure to Genetically Modified Corn: A Report to the U.S. Food and Drug Administration from the Centers for Disease Control and Prevention. Atlanta,GA:Centers for Disease Control and Prevention, 2001.
  31. GURT overview.
  32. "Is Monsanto Going to Develop or Sell "Terminator" Seeds?", paragraph 3
  33. Hybrid varieties and saving seed
  34. Maine becomes second state to require GMO labels, The Washington Post, 10-Jan-2014]
  35. Genetic Literacy Project Infographic: Is labeling GMOs really about our “Right to Know”?
  36. Peer Reviewed Publications on the Safety of GM Foods
  37. Studies for GENERA (as of 5/27/13, there are exactly six hundred studies in this list)
  38. Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects
  39. Quote: 'The science is quite clear: crop improvement by the modern molecular techniques of biotechnology is safe.'
  40. A decade of EU-funded GMO research
  41. Prospect Magazine: The real GM food scandal
  42. Leading Environmental Activist’s Blunt Confession: I Was Completely Wrong To Oppose GMOs
  43. Like this one: Uncovering the Real Story Behind the 'Conversion' of Mark Lynas from Climate Change Journalist to Cheerleader for Genetically Modified Foods, on AlterNet
  44. Biotech-Now: Moms Urged to Subscribe to the ‘Precautionary Principle’ on GMOs
  45. Institute of Science in Society: Use and Abuse of the Precautionary Principle - this is a somewhat outdated defense of the use of the precautionary principle being applied to GE technology.
  46. NaturalNews: Shock findings in new GMO study: Rats fed lifetime of GM corn grow horrifying tumors, 70% of females die early
  47. Institute for Responsible Technology: Are Genetically Engineered Foods Promoting Autism?
  48. Institute for Responsible Technology: Health risks of GMOs
  49. Greenpeace: What's wrong with genetic engineering (GE)?
  50. Sierra Club: Genetic Engineering
  51. WHO: 20 questions on genetically modified foods
  52. ICSU report on GM food
  53. http://www.nationalacademies.org/webextra/crops/
  54. Snell, Chelsea; Bernheim, Aude; Berge, Jean-Baptiste; et al ScienceDirect: Assessment of the health impact of GM plant diets in long-term and multigenerational animal feeding trials: A literature review
  55. Hermosillo, Maribel Monsanto's GMO Seeds Are Actively Cultivating Cultural Genocide PolicyMic
  56. http://www.monsanto.com/newsviews/Pages/terminator-seeds.aspx
  57. http://fbae.org/2009/FBAE/website/our-position-gene-use-restriction-technologies.html
  58. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001415
  59. http://www.ifpri.org/sites/default/files/publications/ifpridp00808.pdf
  60. Kathage, J.; Qaim, M. (2012). "Economic impacts and impact dynamics of Bt (Bacillus thuringiensis) cotton in India". Proceedings of the National Academy of Sciences 109 (29): 11652–6. PMC 3406847. PMID 22753493. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3406847. 
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