6个新的STR基因座复合扩增体系的建立及应用

Construction and Application of Fluorescent-Multiplex PCR of Six New STR Loci

目的构建6个常染色体STR基因座的荧光复合扩增体系,应用于法医学DNA检验。方法筛选6个STR基因座D4S2366、D3S3045、D18S1002、D20S481、D22S689、D4S2639,根据复合扩增要求设计引物并采用不同荧光染料进行标记,经过反复调整和优化,建立6基因座荧光复合扩增体系,并用该复合扩增体系对224名华东汉族无关个体进行分型,计算出常用法医遗传学参数。结果使用该荧光复合扩增体系,在224名华东汉族无关个体中,6个STR基因座D4S2366、D3S3045、D18S1002、D20S481、D22S689、D4S2639分别检出7、8、9、10、9、9个等位基因和21、26、21、23、28、32种基因型,基因型分布符合Hardy-Weinberg平衡。杂合度(H)分布为0.714～0.808,个体识别率(DP)为0.874～0.934,二联体非父排除率(PED)为0.310～0.453,三联体非父排除率(PET)为0.485～0.628,多态信息含量(PIC)为0.672～0.784,二联体累积非父排除率(CPED)为0.947689,三联体累积非父排除率(CPET)为0.993345,累积个人识别能力(CDP)为0.999999543。结论构建的荧光复合扩增体系具有较高的法医学应用价值,D4S2366等6个常染色体STR基因座在华东汉族群体中均具有高度多态性,可作为常规商品化试剂盒的有效补充,用于突变情形的亲权鉴定以及依据亲权指数值不能明确鉴定意见的亲权鉴定。

Objective To establish a multiplex PCR system containing six new STR loci for forensic purposes.Methods Six highly polymorphic STR loci,D4S2366,D3S3045,D18S1002,D20S481,D22S689,and D4S2639,were selected.After PCR with different fluorescence labeled primers,the PCR products from 224 Eastern Han unrelated individuals were analyzed by 3130 Genetic Analyzer.Results Six STR loci were detected by fluorescent-multiplex PCR.Each locus was successfully genotyped in all 224 samples.In D4S2366,D3S3045,D18S1002,D20S481,D22S689,and D4S2639 loci,7,8,9,10,9,9 alleles and 21,26,21,23,28,32 genotypes were observed respectively.The distribution of genotype for six STR loci in the Han population from the east of China was in accordance with Hardy-Weinberg equilibrium.The heterozygosity（H） distributions were 0.714-0.808,the discrimination power（DP） were 0.874-0.934,the probability of exclusion of duos（PEduo） were 0.310-0.453,the probability of exclusion of trios（PEtrio） were 0.485-0.628,and the polymorphic information content（PIC） were 0.672-0.784.The cumulative probability of exclusion（CPE） of duos was 0.947689,the CPE of trios was 0.993345,and the combined discrimination power（CDP） was 0.999999543.Conclusion This six STR multiplex set has high value in forensic application,and it can serve as an effective supplementary of commercial kits.