DXYS267位点的遗传多态性及伴性遗传单核苷酸变异的应用

目的 调查DXYS267基因座遗传多态性，研究该座位伴性遗传单核苷酸的特征及其法医学应用价值。方法 应用聚合酶链反应和聚丙烯酰胺凝胶电泳对DXYS267进行群体调查，并作Hardy-Wein-berg平衡检验，计算法医学群体遗传学参数。依据该基因座伴性遗传的单核苷酸变异，设计新的引物，选择性扩增Y染色体的DXYS267短串联重复序列。结果 在118名中国汉族无关个体中，共发现6个等位基因，基因型频率分布符合Hardy-Weinberg平衡，基因座杂合度为0．6706，个体识别率为0．8433，非父排除率为0．5957。新引物可选择性扩增Y．短串联重复（short tandem repeat，STR）序列，在184名男性无关个体共发现4个等位基因，单倍型多样性值为0．6372。结论 DXYS267属一类X、Y染色体序列同源的STR序列位点，是一个高度多态性的系统。同时利用该位点的伴性单核苷酸变异，选择性扩增Y染色体上的STR序列，用于亲权鉴定和个人识别，尤其是混合斑男性检材的分型和性别鉴定有实用价值。

Polymorphism of DXYS267 locus and application of its Y-specific single nucleotide substitutions

Objective To investigate the polymorphism of DXYS267 locus in China Han population and find the application and characters of its Y-specific single nucleotide substitutions. Methods The locus was analyzed by PCR and PAGE in silver-staining. The Y-specific-STR was amplified with newly designed primers according to the Y-specific single nucleotide substitutions. Results Six alleles were detected in Han population in Wuhan. Exact tests demonstrated that genotype frequencies did not deviate from Hardy-Weinberg equilibrium. Heterozygosity of DXYS267 was 0.6706, discrimination power (DP) was 0.8433, and the probability of paternity exclusion (PE) was 0.5957. The Y-specific-STR of DXYS267 was successfully amplified with the new primer. The 4 alleles for Y-STR were detected with haplotype diversity (HD) 0.6372. Conclusion The DXYS267 locus is appropriate for individual identification and paternity testing. The new primer is useful for individual and paternity testing involving brothers and mixed stains.