Evaluation of the Microhaplotypes panel for DNA mixture analyses
Evaluation of the Microhaplotypes panel for DNA mixture analyses
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DNA 混合物分析的微单倍型面板评估
DOI：
10.1016/j.fsigen.2018.05.003
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发表时间：
2018-07-01
影响因子：
3.1
通讯作者：
Chen, Feng
中科院分区：
文献类型：
--
作者：
Chen, Peng;Yin, Caiyong;Chen, Feng
使用标准短串联重复多态性（STR）试剂盒对DNA混合物中的嫌疑人进行身份鉴定面临挑战。为解决这一问题，已经引入了几种改进的方法或技术。然而，过程中的一些复杂情况仍然难以捉摸。在本研究中，我们提出了一组26个微小微单倍型，每个微单倍型产生相对较高（>3.0）的有效等位基因数（Ae），并且具有较短（<50bp）的序列长度。26个微单倍型在9个群体中的平均Ae和杂合度值分别在2.60 - 4.54和0.59 - 0.96的范围内。鉴别力和非父排除力的值分别在0.49 - 0.87和0.29 - 0.94的范围内。已经发现Ae值与杂合度（r = 0.43，p = 0.02）或鉴别力值（r = 0.55，p = 0.003）之间存在显著正相关。当使用一组Ae = 3的26个微单倍型时，检测两个无关个体混合物的累积概率可达到0.9999998。我们通过大规模平行测序进一步对该组微单倍型进行了测试，在一个单一的多重系统中成功对26个微单倍型中的14个进行了基因分型。对60个无关的中国汉族个体以及2个由两个无关个体混合而成的人工制备样本（一式两份，即4个混合物）进行了测序。在这两个混合物中，14个位点中约32.14%呈现出三个或四个等位基因。认定混合物贡献者的似然比值在1.95×10⁶到1.10×10⁷的范围内。结果表明，本研究提出的这组微单倍型在法医应用中可提供一种有价值的补充工具。
The identification of a suspect in a DNA mixture typed with the standard short tandem repeat polymorphism (STR) kits has faced challenges. Several improved methods or technologies have been introduced to address this issue. However, some complex situations in the process remain elusive. In the present study, we presented a panel of 26 tiny microhaplotypes, each generating a relatively high ( > 3.0) effective number of alleles (A(e)) and possessing low (< 50 bp) sequence lengths. The average A(e) and heterozygosity values among the 9 populations of 26 microhaps were in ranges from 2.60 to 4.54 and 0.59 to 0.96, respectively. Power of discrimination and power of exclusion values were ranged from 0.49 to 0.87 and 0.29 to 0.94, respectively. Significant positive correlations have been found between A(e) values and heterozygosity (r = 0.43, p = 0.02) or power of discrimination values (r = 0.55, p = 0.003), respectively. The cumulative probability of detecting a mixture of two unrelated individuals could reach 0.9999998 when using a panel of 26 microhaps with A(e) = 3. We further tested the panel by using massively parallel sequencing, and 14 out of 26 microhaps were successfully genotyped in a single multiplex system. 60 unrelated Chinese Han individuals and 2 artificially prepared samples mixed by two unrelated contributors (in duplicate, ie. 4 mixtures) were sequenced. Approximately 32.14% of the 14 loci presented three or four alleles in the two mixtures. The likelihood ratio values to cognizance the mixtures' contributor were in a range from 1.95 x 10(6) to 1.10 x 10(7). The results demonstrated that the present panel could offer a valuable complementary tool in forensic applications.