Canadian Journal of Fisheries and Aquatic Sciences, Ahead of Print.
The adaptation of marine and anadromous fishes to novel, freshwater environments requires major physiological shifts in functions related to osmoregulation, immunity, and metabolism. For Atlantic salmon (Salmo salar) populations, such changes have occurred independently in many landlocked populations that were formed as a result of extensive hydrological shifts in North America around 10 000 years ago. We compared patterns of genetic variation between two landlocked and one anadromous population of Atlantic salmon to identify loci that may have played an important evolutionary role in facilitating the transition from an anadromous to an entirely freshwater life history. Outlier loci included single nucleotide polymorphisms (SNPs) in genes related to functions including immunity, growth, and osmoregulation. We also used these same populations to characterize loci associated with distinct hatchery rearing environments. This additional comparison identified outlier SNPs annotated to genes related to wound healing, consistent with findings from other genetic studies of domestication selection in fishes. Together, our results highlight putative responses to both natural selection imposed by major environmental changes and artificial selection levied by differing hatchery environments.

中文翻译：

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适应新环境的基因组特征：内陆和溯河鲑鱼（Salmo salar）的孵化场和生活史相关位点

加拿大渔业和水生科学杂志，印刷前。
海洋和溯河鱼类对新的淡水环境的适应需要在与渗透调节、免疫和新陈代谢相关的功能上发生重大的生理变化。对于大西洋鲑（Salmo salar）种群，这种变化独立发生在许多内陆种群中，这些种群是由于大约 1 万年前北美广泛的水文变化而形成的。我们比较了两个内陆和一个溯河三文鱼种群之间的遗传变异模式，以确定可能在促进从溯河到完全淡水生活史的过渡方面发挥重要进化作用的基因座。异常位点包括与免疫、生长和渗透压调节等功能相关的基因中的单核苷酸多态性 (SNP)。我们还使用这些相同的种群来表征与不同孵化场饲养环境相关的基因座。这种额外的比较确定了与伤口愈合相关的基因注释的异常 SNP，这与鱼类驯化选择的其他遗传学研究的结果一致。总之，我们的结果突出了对重大环境变化所施加的自然选择和不同孵化场环境所施加的人工选择的假定反应。