Department of Biology, University of Maryland, College Park, Maryland 20742, USA.
Evolution. 2010 Feb 1;64(2):486-501. doi: 10.1111/j.1558-5646.2009.00871.x. Epub 2009 Oct 23.
Several models have been proposed to suggest how the evolution of sex-determining mechanisms might contribute to speciation. Here, we describe the inheritance of sex in 19 fish species from the rapidly evolving flock of cichlids in Lake Malawi, Africa. We found that many of these species have a male heterogametic (XY) system on linkage group 7. Some species also segregate for a female heterogametic (ZW) system on linkage group 5 that is coincident with a dominant orange-blotch (OB) color pattern in females. The ZW system is epistatically dominant to the XY system when both are segregating within a family. Several lines of evidence suggest that additional sex-determining loci are segregating in some species. These results are consistent with the idea that genetic conflicts play an important role in the evolution of these species flocks and suggest that evolution of sex-determining mechanisms has contributed to the radiation of cichlid fish in East Africa.
已经提出了几种模型来表明性别决定机制的进化如何促进物种形成。在这里，我们描述了来自非洲马拉维湖快速进化的丽鱼科鱼类中的 19 种鱼类的性别遗传。我们发现，这些物种中的许多具有连锁群 7 上的雄性异配（XY）系统。一些物种还分离出连锁群 5 上的雌性异配（ZW）系统，与雌性中显性的橙色斑点（OB）颜色模式一致。当 XY 系统在一个家庭中分离时，ZW 系统在遗传上对 XY 系统具有显性。有几条证据表明，在一些物种中还存在其他性别决定基因座的分离。这些结果与遗传冲突在这些物种群体的进化中起着重要作用的观点一致，并表明性别决定机制的进化促进了东非丽鱼科鱼类的辐射。
