다음 내용은 특허에 관한내용은 아니지만 biopatent에 가입하신분들은유전자 조작 식품의 안전문제에도 관심이 있으리라 생각하고 올립니다.최근 FEBS letters에 아래와 같은 research article 이 실렸습니다. 아래에 Abstract와 Discussion을 첨부하였습니다. Discussion부분을주목해주십시오.혹시 전문이 필요하신데 구하기 힘든분은 저에게 개인적으로 mail주시기바랍니다.FEBS letters 481:164-168 (15 September 2000)(FEBS: Federation of European Biochemical Societies)—DNA stability in plant tissues: implications for the possible transfer of genes from genetically modified food Amar Chitera, J. Michael Forbesb and G. Eric Blaira, , Edited by Ulf-Ingo Flüggea School of Biochemistry and Molecular Biology, Room 8.10a, Garstang Building, University of Leeds, Mount Preston Street, Leeds LS2 9JT, UKb School of Biology, University of Leeds, Leeds LS2 9JT, UK AbstractThe potential for transfer of antibiotic resistance genes from genetically modified (GM) plant material to microbes through genetic recombination in the human or animal gut is a consideration that has engendered caution in the use of GM foods. This study was aimed at defining the optimal physical and chemical conditions necessary to ensure sufficient fragmentation of DNA in plant tissues to a size where it would be unlikely to be stably transferred to bacterial gut microflora. The ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit (Rubisco SS) genes are of similar size (approximately 1.4 kb) to transgenes present in GM plants. DNA analysis and PCR amplification of Rubisco SS genes showed that fresh maize and maize silage contained high molecular weight DNA and intact Rubisco SS genes. Relatively high temperatures and pressurized steam were necessary to degrade fully genomic DNA and Rubisco SS genes in maize and wheat grains, the source of most animal feedstuffs. Furthermore, chemical expulsion and extrusion of oilseeds resulted in residues with completely degraded genomic DNA. These results imply that stringent conditions are needed in the processing of GM plant tissues for feedstuffs to eliminate the possibility of transmission of transgenes. DiscussionThe results of this study show that treatment of plant tissues at temperatures of 95°C or above for more than a few minutes is sufficient for degradation of DNA to take place to the extent that it should be incapable of transmitting genetic information. These conclusions are based on both the size of DNA fragments and the survival of specific gene sequences, with similar results being obtained in both cases.Two aspects of plant DNA stability have been addressed in this work: on the one hand the extraction of oil, starch and sugar from oilseeds, maize grain and sugar beet, respectively; on the other the heat treatment of maize grains. In the former case, the treatments included chemical and/or physical methods, and where high temperatures were involved, the DNA was broken down into small fragments to the point that specific gene sequences detected by PCR were no longer present. In the case of wet sugar beet pulp, where high temperatures were not incurred, DNA was still intact but when the pulp is dried, DNA was severely fragmented. In the case of wheat grains, a temperature of at least 95°C was required for air-dried grains, while steam treatment significantly reduced the temperature at which fragmentation occurs. From the point of view of the risk of transmission of unwanted genetic determinants from animal or human food, it seems that there is little likelihood of transmission from the extracted oilseed and maize products such as soybean meal and maize gluten, which are the major forms that are traded internationally. For locally produced feedstuffs that are not subjected to high temperatures, such as wet sugar beet pulp, silage and cereal grains, intact DNA is still present and potentially capable of being taken up by microbes in the digestive tract.Our results clearly show that DNA remained stable in silage and so it would seem sensible not to use ensiled GM crops as animal feed in the event of a significant risk of transmission of a transgene from GM source to the gut of farm animals being identified. Although some of the DNA extracted from silage is undoubtedly of microbial origin, the fact that specific Rubisco SS sequences were detected by PCR in silage makes it clear that intact maize DNA was still present.Our results show that if a temperature of 85°C is maintained by steam for 10 min, then DNA is partially fragmented, but some fragments could remain at above the size of a transgene. It will be necessary to carry out further research with material from commercial processing before firm conclusions can be drawn about the viability of DNA in commercial animal feeds.In conclusion, we have shown that processing of plant material involving temperatures of above 95°C for more than a few minutes fragments DNA to the extent that genetic information is unlikely to be retained. Materials which have not been subjected to such treatments not only have non-fragmented DNA but also retain specific PCR-detectable sequences suggesting that DNA is intact. This study therefore has implications for the current debate on the safety of processed GM food consumed by animals and humans.첨부 파일과거 URLhttp://www.ipleft.or.kr/bbs/view.php?board=ipleft_5&id=71