Analysis of Fitness Effect and Its Application in Assessing Environmental Risk Caused by Transgene Flow

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

Abstract

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

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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