三个STR分型体系在法医学中的应用

Application of Three STR Typing Systems in Forensic Medicine

【目的】调查PowerplexTM16 System、STRtyper-10F/G kit以及AGCU 21+1三个分型体系包含的45个常染色体STR基因座在中国广东汉族人群中的群体遗传学数据,评估其法医学应用价值。【方法】采集256例中国广东汉族二代家系(包含512名无关个体)外周血样,提取样本DNA,对D3S1358等45个STR基因座进行扩增,使用ABI 3500XL遗传分析仪电泳扩增产物,GeneMapper ID-X软件进行基因分型,并用相关统计软件计算常用法医学参数并进行Hardy-Weinberg平衡及基因座间连锁不平衡的检验。【结果】经Bonferroni法校正后,45个STR基因座的基因型分布均符合Hardy-Weinberg平衡,不存在连锁不平衡现象。各基因座平均杂合度(Ho)为0.765,平均个体识别力(DP)为0.905,平均多态信息含量(PIC)为0.733。45个STR基因座的累积随机匹配概率(CMP)为9.48×10-50,二联体累积非父排除率(CPEduo)为0.999 999 999 94,三联体累积非父排除率(CPEtri)为0.999 999 999 999 999 990 4。【结论】获得了广东汉族人群45个常染色体STR基因座的群体资料,为广东汉族人群的法医个体识别和亲子鉴定提供了基础数据。联合应用PowerplexTM16 System、STRtyper-10F/G kit和AGCU 21+1系统可以满足突变、单亲、亲缘鉴定等疑难案件的需要。

[Objective] To investigate the genetic polymorphism of 45 autosomal STR loci included in Powerplex^TM 16,STRtyper-10F/G and AGCU 21＋1 systems in Guangdong Han population and assess their value in forensic medicine.[Methods] Samples from 256 two generation pedigrees （including 512 unrelated individuals） were amplified with 3 systems,respectively.The amplified products were separated with ABI 3500XL genetic analyzer and analyzed with GeneMapper ID-X software.The forensic parameters were calculated.Hardy-Weinberg equilibrium of each locus and pairwise linkage disequilibrium were tested.[Results] After the Bonferroni correction,the genotypes of 45 STR loci were in accordance with Hardy-Weinberg equilibrium,no linkage disequilibrium was found.The average Ho of the 45 STR loci was 0.765,the average DP was 0.905 and the average PIC was 0.733.The CMP of the 45 STR loci was 9.48 × 10^-50,the CPEduo was 0.999 999 999 94 and the CPEtri was 0.999 999 999 999 999 990 4.[Conclusion] We obtain the population data of 45 STR loci in Guangdong Han population,providing basic data for forensic personal identification and parental testing.Combining Powerplex^TM 16,STRtyper-10F/G and AGCU 21＋1 systems can meet the requirements in difficult cases such as mutated cases,duo paternity cases and kinship testing.