The term genetically modified organism ( GMO) refers to plants, microbes and animals with genes transferred from other species i

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问题     The term genetically modified organism ( GMO) refers to plants, microbes and animals with genes transferred from other species in order to produce certain novel characteristics (for example resistance to pests, or herbicides) and are produced by recombinant DNA technology. Four main sources of hazards of GMO are discussed by scientists worldwide: 1) those due to the new genes, and gene products introduced; 2 ) unintended effects inherent to the technology; 3) interactions between foreign genes and host genes; and 4) those arising from the spread of the introduced genes by ordinary cross-pollination as well as by horizontal gene transfer.
    GM crops contain material, which is not present in them under natural conditions, and they form a part of our daily diet. To understand what effect they can have on us and on our animals, it is very important to study the influence of those GM plants in different organisms for several generations. At present, these studies are lacking from the scientific literature. Also, several detrimental effects of GM crops had been showed on the metabolism of animals. The hazard of GMO was shown for animals and the environment in many investigations. Earlier it was shown that consumption of GM food by animals led to the negative changes in their organisms. Experiments, conducted by A. Pusztai showed that potatoes modified by the insertion of the gene of snowdrop lectin (雪花莲凝集素 ), stunted the growth of rats, significantly affected some of their vital organs, including the kidneys, thymus (胸腺) , gastrocnemius muscles (腓肠肌) and others and damaged their intestines and their immune system.

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答案转基因生物是指利用基因重组的方法,引入其他物种基因所产生的包含某些新特性(如抗虫或抗除草剂)的植物、微生物和动物。全球科学家列出了转基因生物危害的四大主要来源:(1)新基因以及被引进的基因产品存在的不可预测的隐患;(2)固有的技术产生的非预期效果;(3)外源基因和宿主基因的相互作用;(4)通过普通的异体授粉和水平基因转移所引人的基因的传播。 转基因作物包含在自然状态下不存在的物质,这些作物组成了我们日常饮食的一部分。为了更好地了解转基因植物对人类及其他动物的影响,研究转基因植物对不同生物连续几代的影响尤为重要。当前对转基因植物影响的研究缺乏科学文献的参考。同时某些转基因作物对动物新陈代谢的不利影响已经显现。早期研究发现,动物消费转基因食物之后它们的机体内会发生负面变化。A.Pusztai主导的实验表明,老鼠食用注入了雪花莲凝集素基因的土豆后,生长受到阻碍,它们的主要器官(包括肾、胸腺、排肠肌等)受到极大影响,同时它们的肠和免疫系统也受到损伤。

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