荧光复合扩增4个Y染色体STR的单倍型及其法医学应用

Distribution of Haplotypes for Four Y-STR Loci and Validation in Forensic Science by Using a Double-Fluorescent Multiplex PCR System

目的建立一套Y染色体STR的双色荧光复合扩增系统,调查4个Y-STR基因座单倍型分布情况及其在混合斑物证检验中的法医学应用前景。方法荧光标记引物复合扩增Y-GATA-A10、DYS531、DYS557和DYS448四个Y染色体特异性STR基因座,并用ABⅠ310遗传分析仪对扩增产物进行检测、分型。结果在成都汉族120名无关男性个体中,四个基因座分别检出5、5、8、7个等位基因,共检出78种单倍型,单倍型基因多样性为0.9881。对3例本教研室不能用常规常染色体STR对男性成份作出同一认定的混合斑检材,该系统成功的作出了与嫌疑人血液Y-STR基因型一致的鉴定结论。结论建立的Y-STR荧光标记复合扩增系统具有很高的识别能力,对建立Y染色体STR数据库,研究群体遗传学和进行法医学混合斑物证鉴定有重要意义。

Objective We focus on developing a multiplex PCR system for Y-STR loci that can be detected by double fluorescent system and assessing their usefulness in forensic mixture samples. Methods The primers of four Y-STR loci (DYS-GATA-A10,DYS531,DYS557 and DYS448) amplified by multiplex PCR technique were labeled with fluorescence, then the PCR products of these Y-STRs loci were detecting and typing by ABI PRISM310 Genetic Analyzer. Results When 120 unrelated individuals from the Han population in Chengdu were detected by the system, Y-GATA-A10,DYS531,DYS557 and DYS448 showed 5, 5, 8, 7 alleles, respectively. A total of 78 different haplotypes was identified and the genetic diversity reached 0.9881.To the three cases of mixture stains failed by using conventional autosomal STR analysis, our multiplex system drew conforming conclusion comparing to the suspect′s Y-STRs genotypes. Conclusion Our results show that the multiplex system of four Y-STR will be very powerful for Y-STR database establishing, the paternity testing and mixture stains identifying.