[Genetic polymorphism of 15 short tandem repeats loci of Tibetan nationality and its affinity with other nationalities in Tibet].

OBJECTIVE

To determine the genetic diversity of short tandem repeats (STRs) loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, upsilonWA, TPOX, D18S51, D5S818, and FGA), and to evaluate the genetic structure of Tibetan nationality and its affinity with other Tibetans (Changdu Tibetan, Luoba ethnic group, Deng population) and other Asian populations.

METHODS

Fifteen STRs 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. The genetic distance (D(A)), coefficient of gene differentiation (Gst) values, and heterozygosity (Ht) were estimated using DISPAN. A phylogenetic tree from the allele frequency data at 8 STRs loci and 15 STRs loci obtained from the literature reported previously by using the D(A) and Neighbor-Joining (N-J) method was constructed using MEGA Version 4.0. Multidimensional scaling (MDS) analysis was performed using the SPSS 14.0 software package.

RESULTS

We got 132 alleles in the population studied, with the frequency of 0.0050-0.5990. Ht, the power of discrimination (DP) and the polymorphism information content (PIC) were consistent with the forensic application. Cluster analysis and phylogenic trees revealed that Tibetan nationality had estrangement genetic affinity with other Chinese nationalities and Asian population.

CONCLUSION

The genetic information demonstrates that the 15 chosen gene makers are highly informative loci and are suitable for population genetic research and forensic application.