Genetic pollution

Genetic pollution is undesirable gene flow into wild populations. The term is usually associated with the gene flow from a genetically engineered (GE) organism (or genetically modifed organism - GMO) to a non GE organism; [ [http://www.greenpeace.org/international/campaigns/genetic-engineering/ge-agriculture-and-genetic-pol GE agriculture and genetic pollution] web article hosted by Greenpeace.org] however, conservation biologists and conservationists sometimes use it to describe gene flow from a domestic, feral, non-native or invasive species to a wild population.Potts B. M., Barbour R. C., Hingston A. B., Vaillancourt R. E. (2003) Corrigendum to: TURNER REVIEW No. 6 "Genetic pollution of native eucalypt gene pools—identifying the risks". Australian Journal of Botany 51, 333–333. doi|10.1071/BT02035_CO] Butler D. (1994). Bid to protect wolves from genetic pollution. "Nature" 370: 497 doi|10.1038/370497a0] Use of the term is however controversial.

Genetic engineering

The term "genetic pollution" was popularized by environmentalist Jeremy Rifkin in his 1998 book "The Biotech Century". [Jeremy Rifkin (1998) "The Biotech Century: Harnessing the Gene and Remaking the World", published by J P Tarcher, ISBN 0-87477-909-X] While intentional crossbreeding between two genetically distinct varieties is described as hybridization with the subsequent introgression of genes, Rifkin used genetic pollution to describe the risks that might occur due the unintentional process of genetically modified organisms (GMOs) dispersing their genes into the natural environment by breeding with wild plants or animals. [http://www.fao.org/biotech/C7doc.htm Gene flow from GM to non-GM populations in the crop, forestry, animal and fishery sectors] , Background document to Conference 7: May 31 - July 6, 2002; Electronic Forum on Biotechnology in Food and Agriculture, Food and Agriculture Organization of the United Nations (FAO)] Michael Quinion [http://www.worldwidewords.org/turnsofphrase/tp-gen1.htm “Genetic Pollution”] – World Wide Words] [Amy Otchet (1998) [http://www.unesco.org/courier/1998_09/uk/dires/txt1.htm Jeremy Rifkin: fears of a brave new world] an interview hosted by The United Nations Educational, Scientific and Cultural Organization (UNESCO):Will wars be fought for the control of genes in the 21st century? Jeremy Rifkin fears the worst and explains why]

The usage of genetic pollution by the Food and Agriculture Organization of the United Nations (FAO) is currently defined as: :“"Uncontrolled spread of genetic information (frequently referring to transgenes) into the genomes of organisms in which such genes are not present in nature."”A. Zaid, H.G. Hughes, E. Porceddu, F. Nicholas (2001) [http://www.fao.org/DOCREP/004/Y2775E/y2775e08.htm#bm08 Glossary of Biotechnology for Food and Agriculture - A Revised and Augmented Edition of the Glossary of Biotechnology and Genetic Engineering] . A FAO Research and Technology Paper ISSN 1020-0541. Food and Agriculture Organization of the United Nations. ISBN 92-5-104683-2. Accessed on November 24 2007]

In a 10 years study of four different crops, none of the genetically modified plants were found to be more invasive or more persistent than their conventional counterparts. [M. J. Crawley et al, Nature 409, 682-683 2001 [http://www.nature.com/nature/journal/v409/n6821/abs/409682a0.html] ] An often cited example of genetic pollution is the reputed discovery of transgenes from GE maize in landraces of maize in Oaxaca, Mexico. The report from Quist and Chapela, [cite journal|title=Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico|doi=10.1038/35107068|journal=Nature|volume=414|issue=6863|pages=541–543|year=2001|author=Quist, David] has since been discredited on methodological grounds. [ cite journal|first=Paul|last=Christou|title=No Credible Scientific Evidence is Presented to Support Claims that Transgenic DNA was Introgressed into Traditional Maize Landraces in Oaxaca, Mexico|journal=Transgenic Research|volume=11|issue=1|pages=3–5|year=2002|doi=10.1023/A:1013903300469] The scientific journal that originally published the study concluded that "the evidence available is not sufficient to justify the publication of the original paper." [cite journal|title=Biodiversity (Communications arising): Suspect evidence of transgenic contamination|journal=Nature|year=2002|volume=416|issue=6881|pages=600–601|doi=10.1038/nature738|url=http://www.nature.com/nature/journal/v416/n6881/abs/nature738_fs.html|author=Metz, Matthew|format=dead link|date=June 2008 – ^{[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3A+intitle%3ABiodiversity+%28Communications+arising%29%3A+Suspect+evidence+of+transgenic+contamination&as_publication=Nature&as_ylo=2002&as_yhi=2002&btnG=Search Scholar search]} ] More recent attempts to replicate the original studies have concluded that genetically modified corn is absent from southern Mexico in 2003 and 2004. [S. Ortiz-Garcı´a "et al" 2005, Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004) Proceedings of The National Academy of Sciences 102:p12338-12343 [http://www.pnas.org/cgi/doi/10.1073/pnas.0503356102] ]

A 2004 study performed near a Oregon field trial for a genetically modified variety of creeping bentgrass ("Agrostis stolonifera") revealed that the transgene and its associate trait (resistance to the glyphosate herbicide) could be transmitted by wind pollination to resident plants of different "Agrostis" species, up to 14 km from the test field. [L. Watrud "et al." 2004, "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 101, p.14533.] In 2007, the Scotts Company, producer of the genetically modified bentgrass, agreed to pay a civil penalty of $500,000 to the United States Department of Agriculture (USDA). The USDA alleged that Scotts "failed to conduct a 2003 Oregon field trial in a manner which ensured that neither glyphosate-tolerant creeping bentgrass nor its offspring would persist in the environment". [http://www.usda.gov/wps/portal/usdahome?contentidonly=true&contentid=2007/11/0350.xml]

Invasive species

While in the field of agriculture, agroforestry and animal husbandry "genetic pollution" is being used to describe the undesirable gene flow between GE species and wild relatives; some conservationists are using the term to describe the undesirable gene flow from domestic, feral, non-native and invasive species into indigenous species. For example, TRAFFIC is the international wildlife trade monitoring network which works to ensure that trade in wild plants and animals is not a threat to the conservation of nature. They promote the awareness of the harmful effects of introduced invasive species that may "hybridize with native species, causing genetic pollution". [http://www.traffic.org/wildlife/wild6.htm When is wildlife trade a problem?] hosted by TRAFFIC.org, the wildlife trade monitoring network, a joint programme of WWF and IUCN - The World Conservation Union. Accessed on November 25, 2007:“"Invasive species have been a major cause of extinction throughout the world in the past few hundred years. Some of them prey on native wildlife, compete with it for resources, or spread disease, while others may hybridize with native species, causing “genetic pollution". In these ways, invasive species are as big a threat to the balance of nature as the direct overexploitation by humans of some species."”] The Joint Nature Conservation Committee (JNCC) is the statutory adviser to the Government of United Kingdom and international nature conservation. Its work contributes to maintaining and enriching biological diversity and educating about the harmful effects of the introduction of invasive/non-native species. In this context they have advised that invasive species::"will alter the genetic pool (a process called genetic pollution), which is an irreversible change."” [http://www.jncc.gov.uk/page-1532 Effects of the introduction of invasive/non-native species] - "Joint Nature Conservation Committee (JNCC)", a statutory adviser to Government on UK and international nature conservation. Accessed on November 25, 2007.:“"Occasionally non-native species can reproduce with native species and produce hybrids, which will alter the genetic pool (a process called "genetic pollution"), which is an irreversible change."”]

Controversial term

Whether genetic pollution or similar terms, such as “"genetic deterioration"”, “"genetic swamping"”, “"genetic takeover"” and “"genetic aggression"”, are an appropriate scientific description of the biology of invasive species is debated. Hymer and Simberloff argue that these types of terms::"...imply either that hybrids are less fit than the parentals, which need not be the case, or that there is an inherent value in “pure” gene pools". Rhymer JM and Simberloff, D. (1996) Extinction by Hybridization and Introgression. "Annual Review of Ecology and Systematics" 27: 83-109 doi:10.1146/annurev.ecolsys.27.1.83] They recommend that gene flow from invasive species be termed genetic mixing since::“" "Mixing" need not be value-laden, and we use it here to denote mixing of gene pools whether or not associated with a decline in fitness". Even environmentalists such as Patrick Moore, an ex-member and cofounder of Greenpeace, questions if the term genetic pollution is more political than scientific. In an interview he comments::"If you take a term used quite frequently these days, the term “genetic pollution,” otherwise referred to as genetic contamination, it is a propaganda term, not a technical or scientific term. Pollution and contamination are both value judgments. By using the word “genetic” it gives the public the impression that they are talking about something scientific or technical--as if there were such a thing as genes that amount to pollution." [ [http://www.heartland.org/PrinterFriendly.cfm?theType=artId&theID=14035 What's Wrong with the Environmental Movement: an interview with Patrick Moore] By: Competitive Enterprise Institute staff, "Environment News" 2004 published by The Heartland Institute.]

ee also

* Biodiversity
* Conservation biology
* Eugenics
* Gene pool
* Genetic erosion

References