Forensic characteristics and genetic structure of the Chinese Tibetan population revealed by 38 X-chromosomal InDel loci

With the increasing importance of X-chromosome (Chr-X) genotyping in kinship identification, the exploitation of X chromosome genetic marker multiplex kits is increasing. The Human X-InDels amplification kit is a novel developed system which contained 38 X -chromosomal Insertion/deletion markers (X-InDels) and Amelogenin. Herein, we investigated the genetic diversity of the 38 X-InDels in the Tibetan ethnic minority (n = 792) from seven regions and evaluated the application potential of this novel panel. The rs16368 was the least variable locus, whereas the most polymorphic locus was the rs59605609 in Tibetan population. We confirmed three linkage groups with the haplotype diversities ranged from 0.5032 to 0.5976. The overall combined power of discrimination (PD) in males and females were 0.999999999582066 and 0.999999999999993, respectively. And the overall combined mean exclusion chance (MEC) values were not lower than 0.999125526990159. In addition, we explored the genetic relationships among the Tibetans in seven different regions via series of population comparison analyses, finding that the genetic relationship between the Ngari Tibetan and Chamdo Tibetan was the farthest, which was consistent with geographical distribution.