Haned Hinda, Pène Laurent, Lobry Jean R, Dufour Anne B, Pontier Dominique
CNRS UMR 5558-Laboratoire de Biométrie et Biologie Evolutive, Université Lyon 1, 43 bd du 11 novembre 1918, 69622 Villeurbanne, Cedex, France.
J Forensic Sci. 2011 Jan;56(1):23-8. doi: 10.1111/j.1556-4029.2010.01550.x. Epub 2010 Sep 14.
Determining the number of contributors to a forensic DNA mixture using maximum allele count is a common practice in many forensic laboratories. In this paper, we compare this method to a maximum likelihood estimator, previously proposed by Egeland et al., that we extend to the cases of multiallelic loci and population subdivision. We compared both methods' efficiency for identifying mixtures of two to five individuals in the case of uncertainty about the population allele frequencies and partial profiles. The proportion of correctly resolved mixtures was >90% for both estimators for two- and three-person mixtures, while likelihood maximization yielded success rates 2- to 15-fold higher for four- and five-person mixtures. Comparable results were obtained in the cases of uncertain allele frequencies and partial profiles. Our results support the use of the maximum likelihood estimator to report the number of contributors when dealing with complex DNA mixtures.
在许多法医实验室中，使用最大等位基因计数来确定法医DNA混合样本中的贡献者数量是一种常见做法。在本文中，我们将此方法与Egeland等人先前提出的最大似然估计器进行比较，并将其扩展到多等位基因位点和群体细分的情况。在群体等位基因频率和部分图谱不确定的情况下，我们比较了两种方法识别两到五人混合样本的效率。对于两人和三人混合样本，两种估计器正确解析混合样本的比例均>90%，而对于四人及五人混合样本，似然最大化产生的成功率高出2至15倍。在等位基因频率不确定和部分图谱的情况下也获得了类似结果。我们的结果支持在处理复杂DNA混合样本时使用最大似然估计器来报告贡献者数量。
