Genetic diversity and signatures of selection in 15 Chinese indigenous dog breeds revealed by genome-wide SNPs

There are dozens of recognized indigenous dog breeds in China. However, these breeds have not had extensive studies to describe their population structure, genomic linkage disequilibrium (LD) patterns, and selection signatures. Here, we systematically surveyed the genomes of 169 unrelated dogs that were from15 diverse Chinese dog breeds. Canine 170K SNP chips were used tocompare the genomic structures of Chinese and Western dogs. The genotyping data of 170K SNP chips in Western dogswere downloadedfrom the LUPA (a European initiative of canine genome project) database. Chinese indigenous dogs had lower LD and shorter accumulative runs of homozygosity (ROH) in the genome. The genetic distances between individuals within each Chinese breed were larger than those within Western breeds. Principal component analysis (PCA) and neighbor-joining (NJ)-tree analysis indicated distinct phylogenetic affinities between Chinese and Western dogs. We found evidence for historical introgression of Wester...