Phylogenetic relationships among indigenous sheep populations in East Asia based on five informative blood protein and nonprotein polymorphisms.

The phylogenetic relationships among 23 local sheep breeds and varieties in East Asia were determined based on allele frequency data for five informative and polymorphic blood protein and nonprotein loci (transferrin, arylesterase, hemoglobin-beta, X-protein, and potassium transport) using electrophoresis and ion-densitometric techniques. Comparatively striking differences in the frequency distributions, especially of hemoglobin-beta and X-protein alleles, were seen between the northern population of the Khalkhas, Bhyanglung, Baruwal, Jakar, Sakten, and five Chinese breeds and the southern population of the Bengal, Kagi, Lampuchhre, Myanmar, and Sipsu breeds. Clustering analyses using UPGMA and NJ methods and principal component analysis, using the data of all populations and loci tested, clearly demonstrated the difference. The two population groups are divided by the boundary of the Himalayas, and each diverged into three subgroups: Mongolian, Tibetan, and Himalayan groups in the north and Indian groups I, II, and III in the south. It was noted that the genetic differentiation of populations was more distinct in the northern group. These findings strongly suggest the existence of at least two large and phylogenetically different gene pools of sheep in East Asia.