D7S817、D10S1432、D10S1213及D18S865分型标准物的制备及其遗传多态性研究

目的 利用重组质粒制备四个新的STR基因座(D7S817、DIOS1432、D10S1213及D18S865)的分型标准物，并进行群体遗传学研究。方法 从聚丙烯酰胺凝胶中分离出经PCR扩增后的等位基因片段，二次扩增后纯化的等位基因片段被分别插入到PUC质粒载体中。利用DNA测序证实插入片段大小及结构的正确性后，用国际标准将插入的等位基因片段进行命名。再转染到适当的E．coli DH5α^TM细胞内选择培养，以纯化质粒为模板，扩增出各基因座的等位基因片段后混合。结果 得到四个STR基因座(D7S817、DIOS1432、DIOS1213及D18S865)分型标准物，应用所制备的分型标准物研究汉族和东乡族群体中的基因型分布频率．结论 制备出的四个STR基因座的分型标准物在法科学领域中有很高的应用价值，非常适合于群体遗传学的分析。

A Study on the Construction of Allelic Ladders for 4 Short Tandem Repeat Loci (D7S817, D10S1432, D10S1213 and D18S865) and Their Genetic Pol ymorphism in Two Chinese Populations

OBJECTIVE: To produce standard allelic ladders for four STR loci(D7S817, D10S1432, D10S1213 and D18S865) by recombined plasmids and use them in the research of genetic polymorphism. METHODS: After being amplified by PCR, different STR allelic fragments were isolated from the polyacryramide gel. The STR allelic fragments were eluted into distilled water and reamplified by PCR to obtain purified allelic fragments. Next, the purified allelic fragments were subcloned individually into the PUC plasmid vectors, and the size and structure of the inserts were confirmed by the analysis of their DNA sequences. Then we transfected the PUC plasmid vectors into E. coli DH5 alpha cells, worked on selective culture, and finally, mixed the alleles of the four STR loci respectively. RESULTS: The standard allelic ladders for four new loci (D7S817, D10S1432, D10S1213 and D18S865) were obtained, with which the genetic polymorphisms of four new loci in Chinese Hans and Dongxiang ethnic groups were studied. CONCLUSION: The standard STR allelic ladders acquired by this method are of high value in forensic practice, and they are applicable to the analysis of genetic polymorphism.