Evaluation of a Novel 32 X-STR Loci Multiplex System in the Forensic Application  

32个X-STR荧光复合扩增体系的法医学应用评估

作　　者：ZHANG Juntao YANG Xingyi YU Zhengliang ZHAO Peng LIU Dayu HAN Xiaolong SUN Hongyu LIU Chao 张俊涛;杨幸怡;余政梁;赵鹏;刘大宇;韩晓龙;孙宏钰;刘超(中山大学中山医学院法医系,广州510089;广州市刑事科学技术研究所,广州510080;公安部鉴定中心,北京100038;无锡中德美联生物技术有限公司,江苏无锡214174;国家毒品实验室广东分中心,广州510230)

机构地区：[1]Faculty of Forensic Medicine,Zhongshan School of Medicine,Sun Yat-sen University,Guangzhou 510089,China [2]Guangzhou Forensic Science Institute,Guangzhou 510080,China [3]Institute of Forensic Science,Ministry of Public Security,Beijing 100038,China [4]AGCU ScienTech Incorporation,Wuxi 214174,Jiangsu,China [5]National Anti-Drug Laboratory Guangdong Regional Center,Guangzhou 510230,China

出　　处：《刑事技术》2024年第5期456-463,共8页Forensic Science and Technology

基　　金：广州市科技计划项目(201707010486);广东省自然科学基金(2019A1515011527);广东省刑事技术“双十计划”(2022GDSSGG18)。

摘　　要：The AGCU X Plus STR system is a newly developed multiplex PCR kit that detects 32 X-chromosomal STR loci simultaneously.These are DXS6807,DXS9895,linkage group 1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS10159,DXS10162,DXS10164,DXS7132,linkage group 2(DXS10079,DXS10074,DXS10075),DXS981,DXS6800,DXS6803,DXS6809,DXS6789,DXS7424,DXS101,DXS7133,GATA172D05,GATA165B12,linkage group 3(DXS10103,HPRTB,DXS10101),GATA31E08 and linkage group 4(DXS8377,DXS10134,DXS7423).A major advantage of this kit is that it takes into account linkage between loci,in addition to detecting more X-STR loci.In order to evaluate the forensic application of 32 X-STR fl uorescence amplifi cation system,PCR settings,sensitivity,species specifi city,stability,DNA mixtures,concordance,stutter,sizing precision,and population genetics investigation were evaluated according to the Scientific Working Group on DNA Analysis Methods(SWGDAM)developmental validation guidelines.The study showed that the genotyping results of each locus were signifi cantly accurate when the DNA template was at least 62.5 pg.Complete profi les were obtained for the 1∶1 and 1∶3 combinations.A total of 209 unrelated individuals from Southern Chinese Han community,consisting of 84 females and 125 males,were selected for population studies,and 285 allele profi les were detected from 32 X-STR loci.The polymorphism information content(PIC)ranged from 0.2721 in DXS6800,to 0.9105 in DXS10135,with an average of 0.6798.DXS10135(PIC=0.9105)was the most polymorphic locus,with discrimination power(DP)of 0.9164 and 0.9871 for the male and female.The cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) valu es were all greater than 0.999999999.There were 78 different DXS10103-HPRTB-DXS10101 haplotypes among the 125 males,and the haplotype diversity was 0.9810.There was no signifi cant difference in the cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) values whether considering linkage or not.In summary,the new X-STR multiplex typing system is effective and reliable,which can be uAGCU X Plus STR复合扩增体系是一种可以同时检测X染色体32个基因座分型的新型荧光复合扩增体系,包括DXS6807,DXS9895,X染色体连锁群1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS10159,DXS10162,DXS10164,DXS7132,连锁群2(DXS10079,DXS10074,DXS10075),DXS981,DXS6800,DXS6803,DXS6809,DXS6789,DXS7424,DXS101,DXS7133,GATA172D05,GATA165B12,连锁群3(DXS10103,HPRTB,DXS10101),GATA31E08和连锁群4(DXS8377,DXS10134,DXS7423)。相较于传统试剂盒,它不但可以同时检测更多的X染色体基因座分型,提高系统检验效能,而且考虑了基因座之间的连锁关系。为评估该体系在法医学鉴定中的应用效果,本研究根据SWGDAM验证指南,根据扩增电泳条件、种属特异性、灵敏度、抗抑制剂、精确性、可重复性、一致性、混合样本、Stutter峰和群体多态性等指标对该体系进行全方位评估。结果表明,扩增体系的DNA模板量>62.5 pg时,可获得全部的基因座分型结果。混合检材DNA模板量≥1∶3也可获得完整的次要贡献者的基因分型。在群体多态性研究中,选自南方汉族的209名无关个体共获得285个等位基因,多态信息量(PIC)介于0.2721(DXS6800)~0.9105(DXS10135)之间,平均值为0.6798。多态性信息量最为丰富的基因座是DXS10135(PIC=0.9105),个体识别能力在男、女性群体中分别为0.9164、0.9871。累积个体识别能力在男性及女性群体中均大于0.999999999,在三联体和二联体案件中的累积平均排除概率均大于0.999999999。在125名无关男性个体中存在78个不同的DXS10103-HPRTB-DXS10101单倍型,单倍型多样性为0.9810。在考虑连锁的情况下,计算出的累积个体识别能力(TPD)、三联体和二联体累积平均排除概率相较未考虑连锁时无明显数量级变化。因此,该体系分型准确、可靠,系统检验效能相较传统试剂盒明显提高,可满足法医学实践的要求,可作为常染色体STR复合扩增体系进行法医学鉴定的有效补充。

关 键 词：forensic genetics X-STR loci kinship analysis EVALUATION 

分 类 号：DF795.2[医药卫生—法医学]