北方汉族31个X染色体短串联重复片段突变及遗传多态性研究  

Mutation and Genetic Polymorphism of 31 X-STR Loci in Northern Han Ethnic Group

作　　者：徐妍 刘岩 郝世诚 张金佩 刘革新 陶玉婷 王显众 袁丽 XU Yan;LIU Yan;HAO Shi-cheng;ZHANG Jin-pei;LIU Ge-xin;TAO Yu-ting;WANG Xian-zhong;YUAN Li(Key Laboratory of Evidence Science of Ministry of Education,China University of Political Science and Law,Beijing 100088,China)

机构地区：[1]中国政法大学证据科学教育部重点实验室,北京100088

出　　处：《中山大学学报（医学科学版）》2022年第4期511-521,共11页Journal of Sun Yat-Sen University:Medical Sciences

基　　金：教育部人文社会科学研究规划基金(19YJA820050);中国政法大学“双一流”建设项目(1000-10321021)。

摘　　要：【目的】调查31个X-STR基因座在中国北方汉族的遗传多态性、连锁不平衡情况和突变率。【方法】采集209个中国北方汉族健康志愿者家系样本,用MicroreaderTM 19X和AGCU X19 STR荧光检测试剂盒检测,统计基因座的突变率。选取家系中父亲或母亲各207个样本,组成男性和女性无关个体组并进行遗传多态性研究和连锁不平衡检验。【结果】共检出344个等位基因,基因频率分布在0.0016-0.8100之间。其中多态性信息含量最丰富的基因座是DXS10135(PIC=0.9124)。个体识别能力在男、女群体中分别为0.3305-0.9181、0.5340-0.9876。累积个人识别概率在男、女群体中分别为1-4.5664×10^(-19)、1-1.5784×10^(-31)。平均排除概率在三联体和二联体中分别为0.3127-0.9124、0.1935-0.8446。累积平均排除概率在三联体和二联体中分别为1-2.2819×10^(-17)、1-2.5090×10^(-12)。经分析,有1对X-STR(DXS10103-DXS10101)存在明显连锁不平衡现象。在414次减数分裂中观察到19个X-STR基因座有突变,平均突变率为0.0023,突变率最高的基因座是DXS10135,为0.0121。【结论】获得的31个X-STR遗传学数据为法医学鉴定提供了基础数据。DXS10103-DXS10101存在连锁不平衡,在应用时需按照单倍型频率分析。应用高突变率基因座时需保持谨慎,不要因为个别基因座不符合遗传规律而排除具有某种亲缘关系。【Objective】To investigate the genetic polymorphism,linkage disequilibrium and mutation rate of 31 X-STR loci in the Northern Han Chinese.【Methods】A total of 209 family samples of healthy volunteers in the Northern Han Chinese were selected.All samples were detected by AGCU X19 and MicroreaderTM 19X fluorescence detection kits and the mutation rate of loci was counted.The mothers(n=207)and the fathers(n=207)in the families were selected,respectively,to form the group of unrelated male and female individuals for genetic polymorphism studies and linkage disequilib⁃rium test.【Results】A total of 344 alleles were detected with gene frequencies ranging from 0.0016 to 0.8100.The locus with the most abundant polymorphism information content(PIC)was DXS10135(PIC=0.9124).Discrimination power(DP)was 0.3305-0.9181 and 0.5340-0.9876 in male and female groups respectively.The cumulative discrimination power was 1-4.5664×10^(-19)and 1-1.5784×10^(-31)in male and female groups respectively.Mean exclusion chance(MEC)was 0.3127-0.9124 and 0.1935-0.8446 in trios and duos.The cumulative mean exclusion chance was 1-2.2819×10^(-17)and 1-2.5090×10^(-12)in trios and duos respectively.After analysis,one pair of loci(DXS10103-DXS10101)had obvious linkage disequilibrium.Mutations at 19 X-STR loci were observed in 414 meiotic divisions,with an average mutation rate of 0.0023.DXS10135 had the highest mutation rate of 0.0121.【Conclusion】The obtained 31 X-STR genetic data provid⁃ed basic data for forensic identification.DXS10103-DXS10101 shows linkage disequilibrium,so haplotype frequency could be counted in application.Care should be taken when using loci with high mutation,and don't rule out some kind of kinship only because individual loci do not conform to the laws of inheritance.

关 键 词：X染色体 短串联重复片段 北方汉族 遗传多态性 突变 

分 类 号：D919.4[医药卫生—法医学]