Data from: Parallel signatures of selection in temporally-isolated lineages of pink salmon

Studying the effect of similar environments on diverse genetic backgrounds has long been a goal of evolutionary biologists with studies typically relying on experimental approaches. Pink salmon, a highly-abundant and widely-ranging salmonid, provide a naturally-occurring opportunity to study the effects of similar environments on divergent genetic backgrounds due to a strict two-year semelparous life-history. The species is composed of two reproductively-isolated lineages with overlapping ranges that share the same spawning and rearing environments in alternate years. We used restriction site-associated DNA (RAD) sequencing to discover and genotype approximately 8,000 SNP loci in three population pairs of even- and odd-year pink salmon along a latitudinal gradient in North America. We found greater differentiation within the odd-year than the even-year lineage and greater differentiation in the southern pair from Puget Sound than in the northern Alaskan population pairs. We identified 15 SNPs reflecting signatures of parallel selection using both a differentiation-based method (BAYESCAN) and an environmental correlation method (BAYENV). These SNPs represent genomic regions that may be particularly informative in understanding adaptive evolution in pink salmon and exploring how differing genetic backgrounds within a species respond to selection from the same natural environment.长期以来，探究相似环境对不同遗传背景的影响一直是进化生物学家的核心研究目标，此类研究通常依托实验手段开展。粉鲑（pink salmon）作为一种种群数量庞大、分布范围广泛的鲑科鱼类，因其严格的两年生单次生殖生活史，为探究相似环境对分化遗传背景的影响提供了天然的研究契机。该物种包含两个生殖隔离的支系，二者分布范围重叠，且会在交替年份共享完全一致的产卵与育幼环境。本研究采用限制性酶切位点相关DNA（RAD）测序技术，对北美沿纬度梯度分布的3组偶数年生与奇数年生粉鲑种群配对，开展了约8000个单核苷酸多态性（SNP）位点的发掘与基因分型工作。研究结果显示，奇数年生支系内的遗传分化程度高于偶数年生支系；而来自普吉特湾的南部种群配对，其遗传分化程度也显著高于阿拉斯加北部的两组种群配对。本研究同时采用基于遗传分化的分析方法（BAYESCAN）与环境关联分析方法（BAYENV），共鉴定出15个携带平行选择信号的SNP位点。这些SNP位点所在的基因组区域，可为解析粉鲑的适应性进化机制，以及探究同一物种内不同遗传背景如何响应相同自然环境的选择压力，提供极具参考价值的研究靶点。