Department of Statistics and Actuarial Science, The University of Hong Kong, Hong Kong, China.
Forensic Sci Int Genet. 2018 May;34:81-87. doi: 10.1016/j.fsigen.2018.02.002. Epub 2018 Feb 4.
The Chinese government established a national anti-trafficking DNA database in 2009 to help reunite trafficked children with their families. The database collects DNA information from missing children's parents, trafficked and homeless children, then conducts parentage testing using 18 or more loci to find matched pairs. This article evaluates the matching accuracy of parentage testing in child-trafficking cases, under both Hardy-Weinberg equilibrium and population substructure. Both one-parent and two-parent scenarios are considered, and mutations are taken into account. The number of random matches is first evaluated using exclusion probability (PE). It is found that there are a large number of single parent-child pairs that match at 18 loci, but the PE approach cannot tell which are the true positive ones. The likelihood ratio (LR) approach can help distinguish the true positive matches. So the second step is to obtain the true positive rate and false positive rate of matched pairs of single parent and child according to the LR approach. Based on the results of the two-step procedure, it is concluded that more than 18 loci should be used to ensure a correct match of single parent and child.
中国政府于 2009 年建立了全国反拐卖人口 DNA 数据库，以帮助被拐卖的儿童与家人团聚。该数据库收集失踪儿童父母、被拐卖和流浪儿童的 DNA 信息，然后使用 18 个或更多的基因座进行亲子关系测试，以找到匹配的对。本文评估了亲子关系测试在拐卖儿童案件中的匹配准确性，同时考虑了 Hardy-Weinberg 平衡和群体亚结构。考虑了单亲家庭和双亲家庭两种情况，并考虑了突变。首先使用排除概率 (PE) 评估随机匹配的数量。结果发现，有大量单亲亲子对在 18 个基因座上匹配，但 PE 方法无法区分哪些是真正的阳性匹配。似然比 (LR) 方法可以帮助区分真正的阳性匹配。因此，第二步是根据 LR 方法获得单亲亲子匹配对的真阳性率和假阳性率。基于两步程序的结果，得出结论，应该使用超过 18 个基因座以确保单亲亲子的正确匹配。
