MultipleRetrocopies Recently Derived within Canids.

Abstract

Two transcribed retrocopies of the fibroblast growth factor 4 () gene have previously been described in the domestic dog. Anretrocopy on chr18 is associated with disproportionate dwarfism, while anretrocopy on chr12 is associated with both disproportionate dwarfism and intervertebral disc disease (IVDD). In this study, whole-genome sequencing data were queried to identify otherretrocopies that could be contributing to phenotypic diversity in canids. Additionally, dogs with surgically confirmed IVDD were assayed for novelretrocopies. Five additional and distinctretrocopies were identified in canids including a copy unique to red wolves (). Theretrocopies identified in domestic dogs were identical to domestic doghaplotypes, which are distinct from modern wolfhaplotypes, indicating that these retrotransposition events likely occurred after domestication. The identification of multiple, full lengthretrocopies with open reading frames in canids indicates that gene retrotransposition events occur much more frequently than previously thought and provide a mechanism for continued genetic and phenotypic diversity in canids.