A Recent Canid Breed History

Since the domestication of canids approximately 15,000 years ago a myriad of uses and aesthetics has dominated the selection pressures that have historically been applied to the species. Much debate remains concerning the exact origins of domestication in dogs although extensive research is on-going to elucidate this. A question which has received less attention concerns the more recent history of breeds including the loci exposed to intense phenotypic selection to create breed hallmarks. The formalization and registration of individuals meeting breed standards has created populations which meet specific morphological, behavioral and visual characteristics. These intense breeding practices have resulted in a unique population structure in dogs in which very significant amounts of genetic variation have been partitioned into breeds – more so perhaps than for any other domesticated species. Understanding the genetic history of breeds and elucidating the selected loci is paramount to the understanding of canid selection and the identification of large effect loci. Without a knowledge of the phylogenetic history and directions of gene flow among breeds as well as the major phenotypes that characterize breeds little can be done to identify the loci of large effect which influence phenotypes which differentiate breeds. We propose to perform a high density, genome-wide SNP analysis (170,000 SNPs) in 1,200 individuals representing 65 breeds to identify the relationships among breeds in the recent past (<10,000 years) and to identify the regions of the genome that have been exposed to strong selection in the formation of breeds.