[Genetic polymorphisms of TH01 and VWA loci in Tibetans in China].

OBJECTIVE

To understand the genetic relationship between Han population and Tibetan population, the genetic polymorphisms of two STR loci, TH01 and VWA were studied in the Tibetans in China.

METHODS

EDTA-blood specimens were collected from 89 healthy unrelated Tibetan individuals in Lasa. DNA was extracted using Chelex method. The DNA samples were amplified by PCR technique, and the PAGE horizontal electrophoresis were used to typing the PCR products.

RESULTS

There were five alleles at TH01 locus in Tibetan population. The alleles frequencies were TH016:0.097, TH017:0.227, TH018:0.091, TH019:0.481 and TH019.3:0.104. A total of 12 genotypes were observed in 77 individuals for TH01. For VWA locus there were seven alleles and the allele frequencies were VWA 14:0.101, VWA15:0.034, VWA16:0.208, VWA17:0.303, VWA18:0.208, VWA19:0.129 and VWA20:0.017. A total of 20 genotypes for VWA were observed in 89 individuals. The results of test for Hardy-Weinberg equilibrium showed that the genotype distributions observed at both STR loci were correspondent with those expected(chi-square =7.421 df =8 P>0.05 for TH01; chi-square =19.61 df =14 P>0.05 for VWA).

CONCLUSION

There is no significant difference between Han and Tibetan populations in allele frequencies at TH01 and VWA loci. The results of analysis using genetic distance and phylogenetic tree indicate that Tibetan population is identical with Han population at TH01 and VWA loci .