X染色体上六个短串联重复序列基因座遗传多态性研究

目的研究陕西西安汉族人群6个位于X染色体上的短串联重复序列：DXS7130、DXS1214、DXS6799、DXS6804、DXS7424和DXS7133等位基因及基因型频率分布。方法随机抽取陕西西安汉族118名女性和90名男性无关个体静脉血，提取DNA，PCR扩增，变性聚丙烯酰胺凝胶电泳，银染检测结果。结果在6个基因座中，DXS7130、DXS6799、DXS6804、DXS7424和DXS7133分别检出9个、6个、6个、7个和7个等位基因；SY别检出21、14、15、17和12种基因型；基因频率分别分布在0．0112～0．4101、0．0160～0．4840、0．0050～0．3713、0．0053—0．3632和0．0059～0．5235之间，DXS1214检出8个等位基因，基因频率分布在0．0104～0．3161之间；此6个位点女性的基因型频率分布均符合Hardy—Weinberg平衡。结论此6个X染色体短串联重复序列位点有较高的个体识别率，在个体识别和女孩的亲权鉴定中有应用价值，对疾病相关研究有实际意义。

Genetic polymorphism of six short tandem repeat loci on the X chromosome in a Han race population in China

Objective To investigate the alleles and genotype frequencies of 6 short tandem repeat (STR) loci DXS7130, DXS1214, DXS6799, DXS6804, DXS7424 and DXS7133 on the X chromosome in Chinese Han individuals living in Shaanxi province of Northwest China. Methods The 6 X-chromosomal STR loci were typed by PCR, denatured polyacylamide gel electrophoresis and silver stain. Results Among females from Xi'an Han population, the numbers of alleles in the 5 loci (DXS7130, DXS6799, DXS6804, DXS7424 and DXS7133) were detected to be 9, 6, 6, 7,and 7 respectively; the numbers of genotypes were 21, 14, 15, 17 and 12 respectively; and the number of alleles in the DXS1214 was 8. Exact tests demonstrated that genotype frequencies of females had no departure from Hardy-Weinberg equilibrium. Conclusion The six loci of X-chromosomal STRs are appropriate for individual identification, paternity test involving in female child and for study in related disease.