19个常染色体STR基因座在内蒙古西南汉族人群中的遗传多态性及其应用

Forensic Genetic Study and Application of 19 Autosomal Short Tandem Repeat Loci in the Southwest of Inner Mongolia Han Population

目的调查Goldeneye 20A试剂盒包含的19个常染色体短串联重复序列(short tandem repeats,STRs)基因座在内蒙古西南汉族地区人群中的遗传多态性,观察其在该地区人群中的突变分布,同时针对案件中的三带型现象进行分析。方法应用Goldeneye 20A试剂盒对1 170名内蒙古西南地区汉族无关健康个体进行分型检测,统计分析所含STR基因座的频率分布及群体遗传学参数;应用该试剂盒观察并分析1 109例亲子鉴定中结果为"肯定"的案件的19个常染色体STR基因座的突变情况;针对出现的三等位基因的1例案件,应用Goldeneye 20A试剂盒重复检测,并且使用华夏白金PCR扩增试剂盒进行检测验证。结果 经Bonferroni校正后,19个常染色体STR基因座均符合Hardy-Weinberg平衡检验(P>0.05/19),个体识别率为0.797 6~0.986 7,多态信息含量为0.562 7~0.912 5。累积个体识别率为1-1.4E-23,三联体累积非父排除率为1-6.2E-09,二联体累积非父排除率为1-8.4E-06。1109例亲子鉴定中结果为"肯定"的案件中共发生23次突变,平均突变率为0.832 6×10-3。在19个常染色体STR基因座中,有14个基因座发生突变,D18S51与vWA基因座发生的突变次数最多。1例亲子鉴定中出现Penta D基因座(8/10/11)三带型现象。结论 19个常染色体STR基因座在内蒙古西南地区汉族人群中有良好的遗传多态性,可用于法医遗传学亲权鉴定及个体识别。但STR突变现象较为常见,故应用于今后的亲子鉴定中需谨慎。针对出现的三带型等位基因,需进行认真的判断与验证,从而保证结果的科学性与准确性。

Objective To investigate and analyze the genetic polymorphism,mutation and three-banded patterns of 19 autosomal short tandem repeats loci of Goldeneye 20A kit in Han of the southwest of Inner Mongolia.Methods A total of 1 170 unrelated healthy Han individuals from the southwest of Inner Mongolia population were genotyped with Goldeneye 20A kit.The frequency distribution and the parameter of population genetics of STR loci were analysed statistically.And we also observed 1 109 parentage confirmed cases detected with this kit to obtain the mutation conditions in 19 autosomal STR loci.One case of three-banded pattern was detected with Goldeneye 20A kit and Huaxia platinum kit.Results All the 19 autosomal STR loci were consistent with Hardy-Weinberg equilibrium(P>0.05/19) after Bonferroni’s correction.The power of discrimination (DP) was 0.797 6~0.986 7.The polymorphism information content (PIC) was 0.562 7~0.912 5.The combined discrimination power (CDP) was 1-1.4E-23.The cumulative probability of paternity exclusion for trio (CPET) were 1-6.2E-09,while for duo (CPED) were 1-8.4E-06.23 mutation events were observed at the 14 autosomal STR loci.Among them,the mutation of D18S51 and vWA were the most.The averaged mutation rate was 0.832 6×10-3.One case of tri-allele in Penta D (8/10/11) was genotyped with Goldeneye 20A kit and HuaxiaTM platinum kit.Conclusion All the 19 autosomal STR loci with highly polymorphic in the southwest of Inner Mongolia population can be used for paternity testing and individual identification.We should pay more attention to the paternity testing because of the common mutation and of three-banded patterns STR loci.