Breeding Selection for U.S. Siberian Huskies Has Altered Genes Regulating Metabolism, Endurance, Development, Body...

Background: The Siberian Husky has evolved as a versatile dog capable of traversing over 1600 km in extreme Arctic conditions, being a competitive show dog in the American Kennel Club, or a favorite pet for companionship. Modern genomics provides an opportunity to explore the biological implications of selection within the Siberian Husky breed for the purpose of sledding, show, or pet. Methods: We identified regions of genetic selection associated with sledding, show, or pet purposes using a whole-genome panel of 234 K SNPs from 237 Siberian Huskies. We assessed allelic variation using Wright's F_ST and selective sweeps with runs of homozygosity (ROH). Results: Genomic and morphometric measurement principal component analyses identified population structure aligning with breeding purpose. In total, 118 SNPs demonstrated significant allelic variation (F_ST ≥ 0.6) and 22,598 ROH segments were identified within the Siberian Husky breed. ROH islands (n = 91) highlighted selective sweeps, whereas homozygosity association tests characterized regions of the genome under differential selection between populations. Genes within regions were assessed using GO and KEGG pathway analysis for biological insight. Pet dogs showed selection for olfactory performance genes, whereas show dogs were selected for immune function, tissue and nervous system development, and cytoskeletal motor activity. Sledding Siberian Huskies were selected for the development of muscle organs, lung vasculature, limbs, bones, eye structure, and pigmentation, plus genes influencing lipid metabolism and glucose transport. Conclusions: In all, this provides the first evidence of the biological impact of genetic selection within a breed for the distinct sledding, show, and pet purposes while simultaneously maintaining overall population uniformity to meet breed standards.