DYS19、DYS391、DYS439三个Y-STR荧光标记复合扩增的法医学应用研究

The investigation on forensic application of DYS19, DYS391, DYS439 by multiplex PCR and capillary electro- phoresis

目的 研究Y—染色体STR基因座在法医学检测中的应用价值。方法 用荧光标记DYS19,DYS391,DYS4 39三个Y—STR基因座 ,PCR复合扩增 ,通过毛细管电泳得到结果。结果 三个Y—STR基因座有较高的种属特异性 ;观察 5 0次男性配子细胞形成过程中的减数分裂未发现突变基因 ;对男∶女不同比例混合血样检测 ,当男∶女性血样比达 1∶5 0时 ,仍能准确分型Y—STR基因型 ,并且Y—STR检验较常染色体STR分型更有优势 ;检测了 1～ 15个月病理石蜡切片 ,表明Y -STR基因座适合降解DNA的检测。结论 Y -STR分型适合日常法医检案的需要 ,该方法是对常染色体STR应用的一个补充。

Objective In order to evaluate the value of three Y chromosome STRs in forensic science. MethodsA multiplex PCR to amplify three Y-chomosome STRs loci in the same PCR reaction was set up. PCR products were analyzed using capillary electrophoresis and GeneScan Software on the ABI Prism 310 DNA sequencer. A study of forensic application of three Y-STR loci were also carried out to evaluate the useful value in cases investigation which include determination of the sensitivity, cross reactivity from species samples other than human and genotyping DNA different tissues of the same individual. Furthermore, DNA genotyping of three Y-STR of bloodstain were carried out which different proportion of male and female blood were mixed. ResultsFamily investigation confirmed that DYS19, DYS391, DYS439 were in accordance with Mendelian inheritance. No mutations were detected in 50 meiosis of germline analysis. PCR with mixtures of male/female DNA showed that male component could be found in a ratio up to 1∶50. It was proved that genotyping of Y-STR in some sexual crime should be prior to that of automosomal STR. ConclusionThe results of this paper suggest that three Y-STR loci-DYS19,DYS391,DYS439 are useful markers to indentity males and reconstruction of male lineages in forensic practice.