Comparative Analysis of the Cat Genome Reveals Clues to Feline Domestication

Little is known about the genetic changes that distinguish domestic cat populations from their wild progenitors. Here we describe a domestic cat reference genome assembly as well as comparative inferences made with other cat breeds, wildcats, and other mammals. We provide evolutionary assessments of the feline protein-coding genome, population genetic discoveries surrounding domestication, and a resource of domestic cat genetic variants. Specifically, we identified positively selected genes enriched for genes involved in lipid metabolism that underpin adaptations to a hypercarnivorous diet. We also found positive selection signals within genes underlying sensory processes, especially those affecting vision and hearing in the carnivore lineage. Genomic regions harboring signatures of natural selection that distinguish domestic cats from their wild congeners are enriched in neural crest-related genes associated with behavior and reward in mouse models, as predicted by the domestication syndrome hypothesis, which posits that the morphological and physiological traits modified by mammalian domestication are explained by direct and indirect consequences of mild neural crest cell deficits during embryonic development. Divergence in regions harboring homologous recombination genes may contribute to the high recombination rate reported for domestic cats relative to other mammals and potentially illustrate how domestication may select for an increase in recombination as a mechanism to generate diversity. Taken together, we propose that changes in these genes underlie the evolution of tameness during cat domestication and potentially point to the processes by which cats became domesticated.