考虑突变影响的亲子鉴定研究

目的基于对突变问题的考虑和实验数据,提出达到科学鉴定结论的基本要求,供制定亲子鉴定标准参考。方法检测15个短串联重复序列基因座,包括CSF1 PO、FGA、TH01、TPOX、VWA、D3S1358、D5S818、D7S820、D8S1179、D13S317、D16S539、D18S51、D21S11等13个CODIS基因座以及PentaD和PentaE基因座,统计肯定父权的母亲、孩子、被告男子3人组合和排除父权的母亲、孩子、被告男子3人组合各100例。结果观察到排除父权的母亲、孩子、被告男子3人组合不符合遗传规律的短串联重复序列基因座数。获得了父权指数值的各种分布,包括模拟突变情况下每例父权指数的变化。结论为了避免潜在突变影响,任何情况下都不能仅根据一个遗传标记排除父权。累积非父排除概率和累计父权指数的阈值对于肯定父权和排除父权极为重要。系统的累积非父排除概率和累计父权指数达到一定阈值后,可以获得科学的鉴定结论。在不能达到阈值时,必须通过增加检测的遗传标记数量来达到要求。

A study of paternity testing with considering mutation

Objective To formulate recommendations in the evaluation of results of genetic analyses in paternity testing under considering mutations. Methods A total of 15 short tandem repeat(STR) loci were employed for this study, which were included CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, PentaD and PentaE. Both 100 cases of true trio and 100 cases of false trio were investigated. Results The numbers of mismatch alleles in different STR loci were observed in 100 cases of false trio. The different distributions of paternity index were obtained, including the changes of paternity index in each case of true trio under simulated mutations. Conclusion In order to avoid the effect of mutations, the exclusion of paternity was never considered on the basis of a single locus. The threshold values of the combined probability of exclusion and the paternity index were important for both exclusion and inclusion of paternity. The scientific evidence for paternity testing can be obtained when both the combined probability of exclusion and the paternity index meet the threshold values. However, when either the combined probability of exclusion or the paternity index can not meet the threshold values, more genetic markers should be added.