Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom; email:
Annu Rev Genet. 2014;48:383-403. doi: 10.1146/annurev-genet-120213-092525. Epub 2014 Sep 10.
Genetic recombination affects levels of variability and the efficacy of selection because natural selection acting at one site affects evolutionary processes at linked sites. The variation in local recombination rates across the Drosophila genome provides excellent material for testing hypotheses concerning the evolutionary consequences of recombination. The current state of knowledge from studies of Drosophila genomics and population genetics is reviewed here. Selection at linked sites has influenced the relations between recombination rates and patterns of molecular variation and evolution, such that higher rates of recombination are associated with both higher levels of variability and a greater efficacy of selection. It seems likely that background selection against deleterious mutations is a major factor contributing to these patterns in genome regions in which crossing over is rare or absent, whereas selective sweeps of positively selected mutations probably play an important role in regions with crossing over.
遗传重组会影响变异性水平和选择的效果，因为在一个位点上的自然选择会影响到连锁位点的进化过程。在果蝇基因组中，局部重组率的变化为检验有关重组进化后果的假说提供了极好的材料。本文综述了来自果蝇基因组学和群体遗传学研究的现有知识。连锁位点的选择影响了重组率与分子变异和进化模式之间的关系，使得较高的重组率与较高的变异性水平和更大的选择效果相关联。在那些很少或没有交叉的基因组区域中，背景选择对有害突变的清除可能是导致这些模式的一个主要因素，而对有利突变的选择清除则可能在有交叉的区域中起着重要作用。
