OBJECTIVETo obtain the data in polymorphism distribution of the seven short tandem repeat (STR) loci: D1S2142, D1S3733, D2S1774, D3S2459, D21S1409, D21S1437 and D21S2055 of Chinese Han population in Chengdu, and evaluate the polymorphism data usefulness to the forensic science.

METHODSPCR, polyacrylamide gel electrophoresis (PAGE) and silver staining techniques were used to analyze the DNA samples from unrelated individuals of Chinese Han ethnic group in Chengdu.

RESULTSEleven alleles and twenty-three genotypes were observed in D1S2142. Eight alleles and nineteen genotypes were observed in D1S3733. Eight alleles and fifteen genotypes were observed in D2S1774. Seven alleles and nineteen genotypes were observed in D3S2459. Six alleles and twelve genotypes were observed in D21S1409. Nine alleles and twenty-six genotypes were observed in D21S1437. Twenty alleles and seventy-seven genotypes were observed in D21S2055. The genotype distributions of the seven STR loci showed no deviation from the Hardy-Weinberg equilibrium. The parentage testing of 50 cases revealed an autosomal codominant inheritances and no mutations happened to seven STR loci.

CONCLUSIONThese data indicate that D1S2142, D1S3733, D2S1774, D3S2459, D21S1409, D21S1437 and D21S2055 have good polymorphism, with high probability of exclusion and probability of discrimination power as well as being loci available as the candidate genetic markers to forensic parentage testing and personal identification.