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The MON 810 corn is a genetically modified maize used around the world. It is a ''Zea mays'' line known as YieldGard from the company Monsanto.〔Van Rie J. et al. 1989. Specificity of Bacillius thuringiensis delta-endotoxins. Eur J Biochem 186: 239-247.〕 This plant is a genetically modified organism (GMO) designed to combat crop loss due to insects. There is an inserted gene in the DNA of MON810 which allows the plant to make a protein that harms insects that try to eat it. The inserted gene is from the ''Bacillus thuringiensis'' which produces the Bt toxin that is poisonous to insects in the Lepidoptera order, including the European Corn Borer. These genetically modified plants with Bt toxin are grown on a large scale around the world.〔ISAAA. 2009. Executive Summary Global Status of Commercialized Biotech/GM crops. http://www.isaaa.org/resources/publications/briefs/39/executivesummmary/default.html〕 Monsanto’s corn line MON810 is produced by ballistically transforming another corn line with a plasmid, PV-ZMCT01.〔United States. Environmental Protection Agency. Office of Pesticide Programs. Biopesticides Registration Action Document. N.p., Sept. 2010. Web. 11 Dec. 2012. http://www.epa.gov/oppbppd1/biopesticides/pips/cry1f-cry1ab-brad.pdf〕 This plasmid has a cauliflower mosaic virus 35S promoter and hsp70 maize intron sequences which drive the expression of the Cry1Ab gene. The gene then codes for delta endotoxins (Cry proteins) which are toxins that are very potent and provoke lesions in the cell membrane causing cell death〔Tilley ST, Saibil HR. 2006. The mechanism of pore formation by bacterial toxins. Curr Opin Struct Bio 16:230-236.〕 These produced Bt toxins bind to certain localized sites on the epithelium of the midgut of insects.〔 Proteins need specific receptors on cells in order to form the Cry proteins and become toxic, which is why the toxins are specific for the order Lepidoptera.〔Then, C. 2010. Risk assessment of toxins derived from Bacillus thuringiensis--synergism, efficacy, and selectivity. Environ Sci Pollut Res 17:791-797.〕 The receptors are important for binding the toxic protein and starting the signal cascade, but the exact mechanism of these toxins is not well understood.〔Jimenez-Juarez et al. 2007. Bacillus thuringiensis Cry1Ab mutants affecting oligomer formation are non-toxic to Manduca sexta larvae. J Biol Chem 282 29:21222-21229.〕 == Controversy == MON810’s transgene structure differs from the original plasmid constructed for the safety assessment for Monsanto〔 and has changed compared to the naturally occurring (non-active) Cry1Ab protein.〔Hilbeck A, Schmidt JEU. 2006. Another view on Bt proteins-how specific are they and what else might they do? Biopesticides Int 2 1:1-50.〕 Gilles-Eric Seralini and colleagues (2007 & 2009) re-analyzed Monsanto data for MON810 (which was made available following a demand for public availability of the data, and a court case) and found that it had caused liver, kidney, and heart damage in rats.〔Gilles-Éric Séralini, Cellier D, de Vendomois JS (2007). "New analysis of a rat feeding study with a genetically modified maize reveals signs of hepatorenal toxicity". Arch. Environ. Contam. Toxicol. 52 (4): 596–602〕〔Gilles-Éric Séralini, de Vendômois JS, Roullier F, Cellier D. (2009) A comparison of the effects of three GM corn varieties on mammalian health. Int J Biol Sci. 10;5(7):706-26.〕 However, the European Food Safety Authority (EFSA) reviewed this re-analysis and concluded that the differences observed were within a normal range for control rats and deemed the statistical methods used inappropriate.〔Statement of the Scientific Panel on Genetically Modified Organisms on the analysis of data from a 90-day rat feeding study with MON 863 maize〕 Similar criticisms have been levelled at later work by Séralini involving rats he asserted to have developed cancer from consumption of genetically modified produce; see Séralini affair. Several publications show effects from Cry1Ab on insects and other arthropods not belonging to the group of Lepidoptera.〔Schmidt et al. 2008. Effects of activated Bt transgene products (Cry1Ab, Cry2Bb) on immature stages of the ladybird Adalia bipunctata in laboratory ecotoxicity testing. Arch Environ Contam Toxicol. oi: 10.1007/s00244-008-9191-9.〕〔Hilbeck, A et al. 1998. Toxicity of Bacillis thuringiensis Cry1Ab toxin to the predator Chrysoperla carnea. Environmental Entomology 275:1255-1263.〕〔Bøhn, T., Primicerio, R., Hessen, D. O. and Traavik, T. 2008. Reduced fitness of Daphnia magna fed a Bt-transgenic maize variety. - Archives of Environmental Contamination and Toxicology 55: 584-592.〕〔Bøhn, T., Traavik, T. and Primicerio, R. 2010. Demographic responses of Daphnia magna fed transgenic Bt-maize. - Ecotoxicology DOI 10.1007/s10646-009-0427-x. (Open Access).: 419-430.〕 This indicates an effect on non-target species. Effects on non-target organisms (i.e. those outside the group of Lepidoptera) indicates that the Cry1Ab toxin has less specific modes of toxicity than previously assumed,〔〔 or that the transgene insertion may cause unintended effects (e.g. changes in gene expression) in the plant.〔 On the 5th of April 2012,〔(Poland bans Mon810 )〕 Poland announced that it would ban the cultivation of MON810 on its territory because the "pollen of this strain could have a harmful effect on bees." No evidence exists to suggest that bees are harmed by the Bt Protein, however prior to research implicating neonictinoid pesticides (usage of which is in fact reduced by planting of naturally pesticidal Bt crops〔(Global impact of biotech crops - Environmental effects, 1996–2010 (PDF) )〕), colony collapse disorder was occasionally blamed on modified crops. A 2010 paper (systematic review) by Agnes Ricroch et al. in the journal ''Transgenic Research'', which reviewed several previously published meta-analyses and recent studies, concluded that the German decision to ban the cultivation of MON 810 was "scientifically unjustified." This is despite the fact that several of the meta-analyses reviewed actually indicate specific negative effects from Cry1Ab toxin on non-target organisms,〔Lövei, G. L. and Arpaia, S. 2005. The impact of transgenic plants on natural enemies: a critical review of laboratory studies. - Entomologia Experimentalis et Applicata 114: 1-14.〕〔Lövei, G. L., Andow, D. A. and Arpaia, S. 2009. Transgenic Insecticidal Crops and Natural Enemies: A Detailed Review of Laboratory Studies. - Environmental Entomology 38: 293-306.〕〔Marvier, M., McCreedy, C., Regetz, J. and Kareiva, P. 2007. A Meta-Analysis of Effects of Bt cotton and Maize on Nontarget Invertebrates. - Science 316: 1475-1477.〕 although when compared to spraying with broad-spectrum pesticides, the negative effects on non-target organisms from Cry-toxins were lower.〔 Ricroch et al. claim that substantial evidence cited in their review is biased towards total eco-system effects and the German decision should have been based on a "case-by-case approach" and uses an incomplete list of references. The authors of this review also criticized the French ban and its political circumstances in an ''ISB〔Information Systems for Biotechnology project at Virginia Tech〕 News Report''. As revealed in the WikiLeaks cables, after France banned the variety, Craig Stapleton, the US ambassador to France recommended that "we calibrate a target retaliation list that causes some pain across the EU". In 2012, an article by Bøhn et al., in Environmental Sciences Europe,〔Bøhn, T., Primicerio, R. and Traavik, T. 2012. The German ban on GM maize MON810: scientifically justified or unjustified? - Environmental Sciences Europe 24:22: 1-7.〕 disagreed with the viewpoint of Ricroch et al. that the German ban was “scientifically unjustified”. In drawing their conclusion they point to the following weaknesses in the Ricroch et al. paper: i) important claims about the ''Daphnia magna'' study are incorrect (that the amount of toxin in the experiment was not presented), and ii) core results are omitted from the discussion (overall mortality differences and total fecundity). Furthermore, only selected data from the literature (those showing negative effects) were qualitatively scrutinized – studies showing no effect were simply quantitatively described without their quality being subjected to the same level of critique. The effect of such a double standard in the evaluation of the quality of biosafety science means that those only reading or referring to Ricroch et al. will be seriously misinformed about both the available biosafety science and the German ban on MON810 maize.〔 However, Bøhn et al. do not claim that the ban was finally and irreversibly justified by the science referred to, as this was ultimately seen to be a political decision.〔 A 2012 paper in the Polish Journal of Veterinary Medicine found no difference between the number of honeybees that visited a MON810 maize and a closely related maize. Analysing the controversy over MON810 in Europe and particularly the question of the quality of the biosafety science cited to support the German ban, Wickson and Wynne〔Wickson, F. and Wynne, B. 2012. Ethics of Science for Policy in the Environmental Governance of Biotechnology: MON810 Maize in Europe. - Ethics, Policy and Environment 15: 321-340.〕 have highlighted how science for policy can be differentially framed in terms of its research questions, methods and data interpretation and how all studies performed, whether for or against an issue, can be legitimately debated in terms of the quality of their research process and the significance of their findings. They suggest that debates over the quality of science for policy in the case of MON810 are not purely technical but rather are inherently shaped by unstated normative commitments and value judgments. Finally, they argue that for agricultural biotechnology, there are a range of conditions that make current practices of assessing the quality of biosafety science unethical. These include: a lack of open access to testing materials; limited resources for independent research; lack of transparency concerning the transgenic constructs in use; lack of consistency in the application of evidentiary and interpretive standards; and no clear processes ensuring accountability and consistency in assessment processes.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「MON 810」の詳細全文を読む スポンサード リンク
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