Genetic polymorphisms and haplotypic structure analysis of the Guizhou Gelao ethnic group based on 35 Y-STR loci

•Genetic polymorphisms of 35 Y-STR loci in the Guizhou Gelao group were investigated.•Multi-copy and rapidly mutating Y-STR loci had higher diversity than common loci.•The Gelao group had a close genetic relation to the Han and Miao groups in Guizhou. In this research, 35 Y-chromosomal short tandem repeat (Y-STR) loci were analyzed in 286 unrelated healthy Gelao male individuals from Guizhou Province, China. Allelic and haplotype frequencies, haplotype diversity (HD), haplotype match probability (HMP), and discrimination capacity (DC) values were computed. Pairwise Rst values were assessed by AMOVA analysis and visualized through multidimensional scaling and neighbor-joining tree construction. A total of 609 alleles were detected at the 35 Y-STR loci, and the allelic frequencies ranged from 0.0035 to 0.8322. The HD, HMP, and DC were 0.9999, 0.0036, and 0.9825, respectively. A total of 281 haplotypes were found at 35 loci in the 286 Gelao individuals, 98.25% of which were unique. Related forensic parameters revealed that this panel of 35 loci had a high level of genetic polymorphisms in the Gelao group. However, the use of multi-copy and rapidly mutating Y-STR loci could significantly increase the discrimination power of a common Y-STR panel. Analyses of population differentiation with the same set of common Y-STR loci demonstrated that the Gelao group has a closer genetic relationship with the Guizhou Han and Guizhou Miao groups than other groups.