Insertion/deletion polymorphism (InDel) genetic markers refer to insertion or deletion of DNA fragments into genomic DNA, which have advantages in the identification of degraded samples. In this study, we independently screened 66 highly polymorphic InDel markers from the dbSNP database to establish a multiplex PCR system for forensic DNA identification using next-generation sequencing system (66-plex InDels). We assessed the population genetic data among 251 Chinese Han population using this system and evaluated their potential forensic application. The results showed that all 66 InDel loci conformed to the Hardy-Weinberg equilibrium (P>0.000 758), and all the pairwise InDel loci were in linkage equilibrium after Bonferroni correction. The mean observed heterozygosity (Ho) was 0.482, the mean expected heterozygosity (He) was 0.483,the mean discrimination power (DP) was 0.612, the mean polymorphism information content (PIC) was 0.365, the total discrimination power (TDP) reached 0.999 999 999 999 999 999 999 999 999 428 18. The cumulative power of exclusion for 66 InDel loci was 0.999 739 in duo cases (CPEduo) and was 0.999 999 999 417 in trios cases (CPEtrio). The results show that the 66 InDel loci have high genetic polymorphisms in the Chinese Han population and can be used independently for forensic DNA identification and paternity testing.
插入/缺失多态性(insertion/deletion polymorphism, InDel)遗传标记是一类由DNA片段的插入或者缺失形成的变异形式,在降解检材身份识别领域展现出优势。本文从dbSNP数据库中自主筛选66个InDel基因座,基于高通量测序系统建立了一套多重复合扩增体系(66-plex InDels)。通过评估66-plex InDels在251名中国汉族人群的群体遗传学参数,分析其法医学应用价值。研究结果表明：经过Bonferroni法校正,66个InDel基因座在中国汉族人群中均符合Hardy-Weinberg平衡定律(P>0.000 758),各基因座间处于连锁平衡状态。各基因座平均观测杂合度(Ho)为0.482,平均期望杂合度(He)为0.483,平均个体识别力(DP)为0.612,平均多态性信息含量(PIC)为0.365,累计个体识别率(TDP)为0.999 999 999 999 999 999 999 999 999 428 18。66个InDel基因座的二联体累计非父排除概率(CPEduo)为0.999 739,三联体累计非父排除概率(CPEtrio)为0.999 999 999 417。结果表明：66个InDel基因座在中国汉族人群中具有良好的遗传多态性,可独立应用于法医个体识别和亲权鉴定研究。.
Keywords: Chinese Han population; DNA identification; insertion/delationpolymorphism (InDel); paternity testing.