北京汉族群体39个短串联重复序列基因座多态性及其遗传关系

Genetic variability and phylogenetic analysis of 39 short tandem repeat loci in Beijing Han population

本文首次对北京地区汉族人群的13个CODIS（Combined DNA index system）和26个非CODIS系统STR基因座的遗传多态性进行了研究,建立了北京地区汉族人群39个STR基因座的群体遗传多态性数据库并对其法医学应用价值进行了评价。39个STR基因座的基因型分布均符合Hardy-Weinberg平衡且各基因座之间均不存在连锁现象,个体鉴别力（Power of discrimination,DP）在0.7740-0.9818之间,期望杂合度（Expected heterozygosity,He）在0.6000-0.9350之间,多态性信息含量（Polymorphism information content,PIC）在0.5317-0.9047之间,非父排除率（Power of exclusion,PE）在0.2909-0.8673之间,累积个体鉴别力（Cumulative probability of discrimination,CDP）为0.999999999999999999999999999999999999999964971,累积非父排除率（Cumulative probability of exclusion,CPE）为0.999999999973878。另外,结合已公开报道的国内其他11个群体相应基因座的遗传资料,根据等位基因频率计算遗传距离,构建了系统发生树。本研究可为中国法医DNA数据库和群体遗传学数据库提供重要的基础数据,对北京地区汉族人群开展法医学个体识别、亲权鉴定和遗传学研究具有重要的意义。

In this study, we studied the genetic polymorphisms of short tandem repeat（STR） loci from 13 CODIS and 26 non-CODIS system in Beijing Han population for the first time, and established a database of 39 STR loci whose forensic parameters were further evaluated. Our results demonstrated no significant deviation from the Hardy-Weinberg equilibrium of 39 STR loci and no pairwise linkage disequilibrium between them. The power of discriminations, expected heterozygosity, polymorphic information content, and power of exclusion of 39 STR loci ranged from 0.7740？0.9818, 0.6000？0.9350, 0.5317？0.9047 and 0.2909？0.8673. The cumulated discrimination power and cumulative probability of exclusion were 0.999999999999999999999999999999999999999964971 and 0.999999999973878, respectively. Moreover, the genetic distance was calculated based on allele frequency and phylogenetic tree was built using STR loci data from Beijing Han and other 11 Chinese ethnic groups.This study provides important basic data for Chinese forensic DNA database and population genetics database, and has important significance in carrying out forensic individual identification, paternity testing, and population genetic study.