Genome-wide selection components analysis in a fish with male pregnancy

A major goal of evolutionary biology is to identify the genome-level targets of natural and sexual selection. With the advent of next-generation sequencing, whole-genome selection components analysis provides a promising avenue in the search for loci affected by selection in nature. Here, we implement a genome-wide selection components analysis in the sex-role-reversed Gulf pipefish, Syngnathus scovelli. Our approach involves a double-digest restriction-site associated DNA sequencing (ddRAD-seq) technique, applied to adult females, non-pregnant males, pregnant males and their offspring. An FST comparison of allele frequencies among these groups reveals 47 genomic regions putatively experiencing sexual selection, as well as 468 regions showing a signature of differential viability selection between males and females. A complementary likelihood ratio test identifies similar patterns in the data as the FST analysis. Sexual selection and viability selection both tend to favor the rare allel...

进化生物学的核心目标之一，是鉴定自然选择与性选择在基因组层面的作用靶点。随着下一代测序（next-generation sequencing）技术的兴起，全基因组选择成分分析为搜寻自然界中受选择影响的基因座提供了极具前景的研究途径。本研究针对性角色反转的海湾尖嘴鱼（Syngnathus scovelli）开展了全基因组范围的选择成分分析：我们采用双酶切限制性位点关联DNA测序（double-digest restriction-site associated DNA sequencing, ddRAD-seq）技术，对成年雌性、非妊娠雄性、妊娠雄性及其子代进行测序。通过对上述群体间的等位基因频率开展FST（群体分化指数）比较分析，结果显示47个基因组区域疑似受到性选择作用，另有468个基因组区域呈现雌雄个体间差异存活选择的特征。补充的似然比检验（likelihood ratio test）分析也得到了与FST分析一致的数据模式。性选择与存活选择均倾向于青睐稀有等位基因……