Genetic polymorphisms for 19 autosomal STR loci of Chongqing Han ethnicity and phylogenetic structure exploration among 28 Chinese populations

The allele frequencies and forensic statistical parameters of 19 autosomal short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSF1P0, D3S1358, THOl, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, FGA, D6S1043, Penta D, Penta E, and D12S391) included in the Goldeneye T DNA ID system 20A kit were obtained in 671 Chinese Han individuals residing in Chongqing, Southwest China. All 19 STR loci were identified in agreement with the Hardy-Weinberg equilibrium. A total of 238 alleles were observed with corresponding allele frequencies that varied from 0.0007 to 0.5119. The combined power of discrimination and the combined probability of exclusion for 19 STR loci in the Chongqing Han population were 0.99999999999999999999998954 and 0.99999998387, respectively. The findings indicated that the 19 autosomal STR loci were highly polymorphic in the Chongqing Han population and can be used as a powerful tool in personal identification and parentage testing. Our genetic study enriched the Chinese local forensic reference database. Population comparisons and phylogenetic analyses revealed that genetic heterogeneity widely existed among the Chongqing Han, Xinjiang Uyghur, and Kazakh populations as well as demonstrated that genetic similarity was tightly associated with those of close geographic origin or of the same ethnic origin.