Comparative population genomics of Arctic sled dogs reveals a deep and complex history

Recent evidence demonstrates genomic and morphological continuity in the
Arctic ancestral lineage of dogs. Here, we use the Siberian Husky to
investigate the genomic legacy of the northeast Eurasian Arctic lineage
and model the deep population history using genome-wide SNPs. Utilizing
ancient dog calibrated molecular clocks, we found that at least two
distinct lineages of Arctic dogs existed in ancient Eurasia at the end of
the Pleistocene. This pushes back the origin of sled dogs in the northeast
Siberian Arctic with humans likely intentionally selecting dogs to perform
different functions and keeping breeding populations that overlap in time
and space relatively reproductively isolated. In modern Siberian Huskies,
we found significant population structure based on how they are used by
humans, recent European breed introgression in about half of the dogs that
participate in races, moderate levels of inbreeding, and fewer potentially
harmful variants in populations under strong selection for form and
function (Show, Sled-Show, and Racing populations of Siberian Huskies). As
the struggle to preserve unique evolutionary lineages while maintaining
genetic health intensifies across pedigreed dogs, understanding the
genomic history to guide policies and best practices for breed management
is crucial to sustain these ancient lineages and their unique evolutionary
identity.