RESUMO
<p><b>OBJECTIVE</b>To investigate the genetic polymorphism of 15 autosomal short tandem repeat (STR) loci, i.e. D5S818, FGA, D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX and D18S51, in Tibetan population of Changdu area, and to analyze the genetic relationship between this population and other Asian populations.</p><p><b>METHODS</b>The 15 loci were amplified simultaneously using a multiplex PCR typing system. Amplified STR fragments were analyzed with an ABI PRISM 3100 Avant DNA Analyzer. Arlequin software version 3.1 was used to obtain allele frequencies and polymorphism parameters.</p><p><b>RESULTS</b>There were 135 STR alleles in the 15 STRs of Changdu Tibetan, with allele frequencies ranging from 0.0065 to 0.5455. The average heterozygosity was 0.7340, the discrimination power was higher than 0.8 except for TPOX and TH01. The accumulative discrimination power was more than 0.9999998, and the accumulative non-parental exclusion probability was 0.99999997.</p><p><b>CONCLUSION</b>The 15 STR loci of Changdu Tibetan possess characteristics of high genetic diversity. They can be employed in minority genetics investigation, and individual and paternity test in forensic medicine.</p>