Abstract: [Abstract] Objective Studing HPRTB、DXS6803 and DXS6809 STR loci genetic polymorphism in Tianjin Han female population ,to provide experimental data in the prenatal diagnosis of aneuploidies accurately and rapidly. Methods A total of 150 samples were collected in Tianjin Han population .QF-PCR and capillary electrophoresis was applied.The relevant data were analyzed by ABI Prism GeneMapper v3.0 software. From each locus selected 2 homozygotes sequence named .The frequencies of the genotypes were checked using Chi-square test to verify Hardy-Weinberg Equilibrium (P＞0.05). Genetic polymorphisms data were calculated by PowerStatsV12 software. Result 150 samples were successfully amplified in 24 hours.10、6、10 alleles and 22、12、29 genotype were found respectively in HPRTB, DXS6803 and DXS6809 locus.The most common allele were 14,13,14.The highest frequency of genotype were 14-14,12-13 and 13-14.No significant deviations from the Hardy-Weinberg equilibrium were observed in these three STR loci(χ2 was 10.554,5.783 and 15.355,respectively,P>0.05).The He of these three STR loci was 0.748,0.649,0.806 respectively.The Ho was 0.607,0.700,0.713 respectively.The PIC was 0.706,0.599,0.775 respectively.The PD was 0.894,0.814,0.931 respectively.The PE was 0.299,0.428,0.449 respectively.Conclusions HPRTB, DXS6803 and DXS6809 STR loci were highly polymorphic. which are favorable genetic markers on chromosome X and can be used in rapid prenatal genetic diagnosis .

Key words: [Key words] chromosome X, STR loci, genetic polymorphism, quantitative fluorescence polymerase chain reaction, Tianjin Hanpopulation