Lenski R E
Center for Microbial Ecology, Michigan State University, East Lansing 48824-1325.
Experientia. 1993 Mar 15;49(3):201-9. doi: 10.1007/BF01923527.
Genetically modified microorganisms hold great promise for environmental applications. Nonetheless, some may have unintended adverse effects. Of particular concern for risk assessment is the simple fact that microorganisms are self-replicating entities, so that it may be impossible to control an adverse effect simply by discontinuing further releases of the organism. It has been suggested, however, that genetically modified microorganisms will be poor competitors and therefore unable to persist in the wild due to energetic inefficiency, disruption of genomic coadaptation, or domestication. Many studies support the hypothesis that genetically modified microorganisms are less fit than their progenitors, but there are a few noteworthy counter-examples in which genetic modifications unexpectedly enhance competitive fitness. Furthermore, subsequent evolution may eliminate the maladaptive effects of some genes, increasing the likelihood that a modified organism or its engineered genes will persist. Evaluating the likelihood that a genetically modified microorganism or its engineered genes will persist is a complex ecological and evolutionary problem. Therefore, an efficient regulatory framework would require such evaluations only when there are plausible scenarios for significant adverse environmental effects.
转基因微生物在环境应用方面极具前景。尽管如此，有些可能会产生意想不到的不利影响。对于风险评估而言，特别值得关注的一个简单事实是，微生物是自我复制的实体，因此，仅仅通过停止该生物体的进一步释放可能无法控制其不利影响。然而，有人提出，转基因微生物将是竞争力较弱的竞争者，因此由于能量效率低下、基因组共适应的破坏或驯化，它们无法在野外生存。许多研究支持转基因微生物比其祖先适应性更差的假设，但也有一些值得注意的反例，其中基因改造意外地提高了竞争适应性。此外，后续的进化可能会消除某些基因的不良适应效应，增加改造后的生物体或其工程基因持续存在的可能性。评估转基因微生物或其工程基因持续存在的可能性是一个复杂的生态和进化问题。因此，一个有效的监管框架仅在存在重大不利环境影响的合理情景时才需要进行此类评估。
