OBJECTIVETo know the genotype and allele frequency distribution of D1S549, D3S1754 and D12S375 in Chinese Han population in the Qingdao area and to study the three short tandem repeat(STR) loci for genetic application.

METHODSACD-blood specimens were collected from the unrelated individuals in Qingdao. The DNA samples were extracted with the use of Chelex method and were amplified by polymerase chain reaction (PCR) technique. The PCR products were analyzed by polyacrylamide gel electrophoresis and were visualized by silver staining.

RESULTSEight alleles were found at D1S549 locus, eight alleles at D3S1754 locus and five alleles at D12S375 locus, and 22, 19 and 14 genotypes were identified respectively. No deviation from Hardy-Weinberg equilibrium was observed in the three loci. The heterozygosities expected of them were 0.7988, 0.7087 and 0.75 respectively. The exclusion probability was calculated as 0.6592 for D1S549, and 0.5605 for D3S1754, and 0.5864 for D12S375. The discriminating power of the three loci were 0.9143, 0.8382 and 0.8861. Comparison of the allelic frequencies in Qingdao area with those in Hans of Chengdu area by chi-square test showed a difference statistically significant at D1S549 locus but no difference at D3S1754 and D12S375 loci.

CONCLUSIONThis study reveals the structure of the three loci and the obtained data are beneficial to understanding the population genetics in Chinese Han population. All of the three loci have higher chance of exclusion and higher discriminating power, and they will be useful markers for individual identification, paternity test and genetics purposes.