Abstract: Objective To investigate the genetic polymorphism of 7 Y-STR loci and haplotypes in Tibetan population. Methods The DNA samples from 67 Tibetan men were analyzed by PCR and the denatured PAGE followed by silver staining. Results 25 alleles were identified for 6 loci including DYS393 ,DYS389Ⅰ,DYS19, DYS390, DYS389Ⅱ and DYS392, 22 alleles were identified for DYS385, the frequency distributions were between 0.014 9～0.507 5, the DP value distributions were between 0.507 5～0.899 1, the DP value of DYS 385 was the highest. 51 haplotypes were identified for the YH6 system which consisted of the 7 loci, the DP value of this system was 0.988 7, the alleles for DYS393 and DYS389Ⅱ were few ,it followed that perhaps Tibetan population had met with bottleneck event in their evolution process. Conclusion The 7 STR loci above belong to loci of high discriminating ability, the haplotypes are highly polymorphic.

Key words: Y-STR, genetic polymorphism, individual identification, haplotype