Garner Austin G, Goulet Benjamin E, Farnitano Matthew C, Molina-Henao Y Franchesco, Hopkins Robin
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 021382, USA.
The Arnold Arboretum, Harvard University, Boston, MA 02131, USA.
Genes (Basel). 2018 Apr 3;9(4):191. doi: 10.3390/genes9040191.
Reinforcement is the process by which selection against hybridization increases reproductive isolation between taxa. Much research has focused on demonstrating the existence of reinforcement, yet relatively little is known about the genetic basis of reinforcement or the evolutionary conditions under which reinforcement can occur. Inspired by reinforcement's characteristic phenotypic pattern of reproductive trait divergence in sympatry but not in allopatry, we discuss whether reinforcement also leaves a distinct genomic pattern. First, we describe three patterns of genetic variation we expect as a consequence of reinforcement. Then, we discuss a set of alternative processes and complicating factors that may make the identification of reinforcement at the genomic level difficult. Finally, we consider how genomic analyses can be leveraged to inform if and to what extent reinforcement evolved in the face of gene flow between sympatric lineages and between allopatric and sympatric populations of the same lineage. Our major goals are to understand if genome scans for particular patterns of genetic variation could identify reinforcement, isolate the genetic basis of reinforcement, or infer the conditions under which reinforcement evolved.
强化是指针对杂交的选择增加分类群之间生殖隔离的过程。许多研究都集中在证明强化的存在上，但对于强化的遗传基础或强化能够发生的进化条件却知之甚少。受强化在同域中而非异域中生殖性状分化的典型表型模式的启发，我们讨论强化是否也会留下独特的基因组模式。首先，我们描述了因强化而预期出现的三种遗传变异模式。然后，我们讨论了一组可能使在基因组水平上识别强化变得困难的替代过程和复杂因素。最后，我们考虑如何利用基因组分析来判断强化是否以及在何种程度上在同域谱系之间以及同一谱系的异域和同域种群之间的基因流情况下进化。我们的主要目标是了解对特定遗传变异模式的基因组扫描是否能够识别强化、分离强化的遗传基础，或推断强化进化的条件。
