Homozygosity mapping in the Kazakh national dog breed Tazy

The identification of runs of homozygosity (ROH) is an informative approach to assessing the history and possible patterns of directional selection pressure. To our knowledge, the present study is the first to provide an overview of the ROH pattern in the Kazakh national dog breed Tazy from a genome-wide perspective. A total of 1699 homozygous segments were identified in 39 Tazy dogs. The ROH consisted mainly of shorter segments (1-2 Mb), which accounted for approximately 67% of the total ROH. The estimated inbreeding coefficients of the ROH ranged from 0.028 to 0.058 with a mean of 0.057. Five hot genomic regions were identified on chromosomes 18, 22, and 25 that overlapped with regions of hunting traits in other hunting breeds. Among the 12 candidate genes located in these regions, the gene CAB39L may be a candidate that affects running speed and endurance of the Tazy dog. Eight genes could belong to an evolutionarily conserved complex as they were clustered in a large protein network with strong linkages. The results may enable effective interventions when incorporated into conservation planning and selection of the Tazy breed.