适合度分析对转基因逃逸潜在环境风险评价的意义

doi:10.13560/j.cnki.biotech.bull.1985.2015.03.007

摘要/Abstract

摘要： 转基因作物的全球大规模种植引起了全世界的广泛关注甚至争议。经过遗传改良并具有自然选择优势的转基因作物进入商品化种植，可能将带来环境生物安全的顾虑。在这些生物安全的顾虑中，转基因通过花粉介导的基因漂移向栽培作物的野生近缘种逃逸及其导致的潜在环境风险，就是世人最为关注的环境生物安全问题之一。包括中国在内的许多国家，在转基因作物进行商品化生产之前都必须对转基因逃逸及其带来的潜在环境风险进行严格评价。按照风险评价的框架，转基因向野生近缘种逃逸及其带来潜在环境风险的评价包括3个连续的步骤：1）检测转基因漂移到作物野生近缘种的频率；2）分析转基因在野生近缘种中的表达；3）确定转基因对野生近缘种群体适合度和进化潜力的影响。大量基因漂移的研究结果已表明，转基因通过基因漂移向栽培作物邻近的野生近缘种群体逃逸难以避免，而转基因也会在作物的野生近缘种群体中正常表达。因此分析和评价转基因为野生近缘种带来的适合度效应，对于转基因逃逸及其环境风险的评价至关重要。对适合度的概念及其进化意义进行介绍，并对如何利用转基因的适合度效应分析转基因逃逸的环境风险，以及对此类环境风险进行研究和评价的具体方法予以介绍。上述知识和方法的掌握将有助于人们对转基因作物环境生物安全及其评价的全面理解。

关键词: 生物安全, 转基因逃逸, 生态风险评价, 转基因生物, 适合度效应, 进化潜力

Abstract: The extensive commercial cultivation of genetically engineered（GE）crops with novel genes and natural selection-advantageous traits has aroused tremendous concerns and even debate over the biosafety issues worldwide. Among these, environmental risk caused by transgene escape from GE crops to their wild and weedy relatives is a long-standing biosafety issue. In many countries including China, the assessment of transgene escape and its potential environmental risks is required before the GE crops are released for commercial cultivation. Following the biosafety assessment framework, the assessment of environmental risks caused by transgene escape commonly includes three consecutive steps. That is to assess the frequency of transgene flow from a GE crop to its wild relatives；the expression of transgenes in wild relatives；and the ecological impact of the transgenes. A large number of studies for（trans）gene flow in many crops has been conclude, which indicated that transgene escape from GE crops to their wild relatives in the vicinity through pollen-mediated gene flow is not inevitable. Transgenes can also normally express in wild relatives. It is therefore essential to assess the fitness effect of a transgene in populations of wild relatives, which is a critical determinant for the environmental impact caused by transgene escape. In this review, the author will introduce the concept and evolutionary significance of fitness, and how to analyze the fitness effect of a transgene for assessing the environmental risks caused by transgene escape from a GE crop to its wild relatives. The knowledge will facilitate our understanding in relation to how environmental biosafety of a GE crop is assessed.

Key words: biosafety, transgene escape, ecological-risk assessment, genetically engineered organism, fitness effect, evolutionary potential

卢宝荣. 适合度分析对转基因逃逸潜在环境风险评价的意义[J]. 生物技术通报, 2015, 31(4): 7-16.

Lu Baorong. Analysis of Fitness Effect and Its Application in Assessing Environmental Risk Caused by Transgene Flow[J]. Biotechnology Bulletin, 2015, 31(4): 7-16.

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