Conner A J, Jacobs J M
New Zealand Institute for Crop and Food Research, Private Bag 4704, Christchurch, New Zealand.
Mutat Res. 1999 Jul 15;443(1-2):223-34. doi: 10.1016/s1383-5742(99)00020-4.
The benefits of genetic engineering of crop plants to improve the reliability and quality of the world food supply have been contrasted with public concerns raised about the food safety of the resulting products. Debates have concentrated on the possible unforeseen risks associated with the accumulation of new metabolites in crop plants that may contribute to toxins, allergens and genetic hazards in the human diet. This review examines the various molecular and biochemical mechanisms by which new hazards may appear in foods as a direct consequence of genetic engineering in crop plants. Such hazards may arise from the expression products of the inserted genes, secondary or pleiotropic effects of transgene expression, and random insertional mutagenic effects resulting from transgene integration into plant genomes. However, when traditional plant breeding is evaluated in the same context, these mechanisms are no different from those that have been widely accepted from the past use of new cultivars in agriculture. The risks associated with the introduction of new genes via genetic engineering must be considered alongside the common breeding practice of introgressing large fragments of chromatin from related wild species into crop cultivars. The large proportion of such introgressed DNA involves genes of unknown function linked to the trait of interest such as pest or disease resistance. In this context, the potential risks of introducing new food hazards from the applications of genetic engineering are no different from the risks that might be anticipated from genetic manipulation of crops via traditional breeding. In many respects, the precise manner in which genetic engineering can control the nature and expression of the transferred DNA offers greater confidence for producing the desired outcome compared with traditional breeding.
作物植物基因工程在提高全球粮食供应的可靠性和质量方面的益处，与公众对由此产生的产品食品安全问题的担忧形成了对比。争论主要集中在与作物植物中新代谢物积累相关的可能无法预见的风险上，这些新代谢物可能会导致人类饮食中的毒素、过敏原和基因危害。本综述探讨了作物植物基因工程直接导致食品中可能出现新危害的各种分子和生化机制。此类危害可能源于插入基因的表达产物、转基因表达的次级或多效性效应，以及转基因整合到植物基因组中产生的随机插入诱变效应。然而，当在相同背景下评估传统植物育种时，这些机制与过去农业中使用新品种时已被广泛接受的机制并无不同。与通过基因工程引入新基因相关的风险，必须与将相关野生物种的大片染色质渗入作物品种的常见育种实践一并考虑。这种渗入的DNA中有很大一部分涉及与感兴趣的性状（如抗虫或抗病）相关的功能未知的基因。在这种情况下，基因工程应用带来新的食品危害的潜在风险，与通过传统育种对作物进行基因操作可能预期的风险并无不同。在许多方面，与传统育种相比，基因工程能够控制转移DNA的性质和表达的精确方式，为产生预期结果提供了更大的信心。
