24 Y-chromosomal STR haplotypic structure for Chinese Kazak ethnic group and its genetic relationships with other groups.

The Kazak ethnic minority is a large ethnic group in the Xinjiang Uygur Autonomous Region of China and is valuable resource for the study of ethnogeny. In the present study, 24 Y-chromosomal short tandem repeat (Y-STR) loci were analyzed in 201 unrelated Kazak male individuals from Ili Kazak Autonomous Prefecture, Xinjiang, China. The gene diversity of the 24 Y-STR loci in the studied Kazak group ranged from 0.0050 to 0.9104. According to haplotypic analysis of the 24 Y-STR loci, 113 different haplotypes were obtained, 96 of which were unique. The haplotype diversity and discrimination capacity in Kazak group were 0.9578 and 0.5622 at 24 STR loci, respectively. The haplotype diversity and discrimination capacity at Y-filer 17 loci, extended 11 loci, and minimal 9 loci were reduced to 0.9274 and 0.4279, 0.8459 and 0.3284, and 0.8354 and 0.2985, respectively, which could indicate that the more loci were detected, the higher forensic efficacy was obtained. We evaluated the application value of the 24 loci in forensic sciences and analyzed interpopulation differentiations by making comparisons between the Kazak1 (represent our samples from Ili Kazak Autonomous Prefecture) group and other 14 groups. The results of pairwise genetic distances, multidimensional scaling plot, and neighbor-joining tree at the same set of 17 Y-filer loci indicated that the Kazak1 group had the closer genetic relationships with Kazak2 (represent samples from the whole territory of Xinjiang Uygur Autonomous Region), Mongolian, and Uygur ethnic groups. The present results may provide useful information for paternal lineages in forensic cases and can also increase our understanding of the genetic relationships between Kazak1 and other groups.