Budowle Bruce, Ge Jianye, Chakraborty Ranajit, Gill-King Harrell
Institute of Investigative Genetics, 3500 Camp Bowie Blvd, University of North Texas Health Science Center, Fort Worth, TX, 76102, USA.
Investig Genet. 2011 Jun 27;2(1):15. doi: 10.1186/2041-2223-2-15.
Identification of missing persons from mass disasters is based on evaluation of a number of variables and observations regarding the combination of features derived from these variables. DNA typing now is playing a more prominent role in the identification of human remains, and particularly so for highly decomposed and fragmented remains. The strength of genetic associations, by either direct or kinship analyses, is often quantified by calculating a likelihood ratio. The likelihood ratio can be multiplied by prior odds based on nongenetic evidence to calculate the posterior odds, that is, by applying Bayes' Theorem, to arrive at a probability of identity. For the identification of human remains, the path creating the set and intersection of variables that contribute to the prior odds needs to be appreciated and well defined. Other than considering the total number of missing persons, the forensic DNA community has been silent on specifying the elements of prior odds computations. The variables include the number of missing individuals, eyewitness accounts, anthropological features, demographics and other identifying characteristics. The assumptions, supporting data and reasoning that are used to establish a prior probability that will be combined with the genetic data need to be considered and justified. Otherwise, data may be unintentionally or intentionally manipulated to achieve a probability of identity that cannot be supported and can thus misrepresent the uncertainty with associations. The forensic DNA community needs to develop guidelines for objectively computing prior odds.
大规模灾难中失踪人员的身份识别基于对多个变量的评估以及对源自这些变量的特征组合的观察。如今，DNA分型在人类遗骸的身份识别中发挥着更为突出的作用，对于高度腐败和碎片化的遗骸尤其如此。通过直接分析或亲属关系分析得出的基因关联强度通常通过计算似然比来量化。似然比可以乘以基于非基因证据的先验概率，以计算后验概率，也就是说，通过应用贝叶斯定理来得出身份认定的概率。对于人类遗骸的身份识别，需要理解并明确有助于先验概率的变量集和交集的形成路径。除了考虑失踪人员的总数外，法医DNA领域在明确先验概率计算的要素方面一直保持沉默。这些变量包括失踪人员的数量、目击者陈述、人类学特征、人口统计学信息及其他识别特征。需要考虑并论证用于确定将与基因数据相结合的先验概率的假设、支持数据和推理。否则，数据可能会被无意或有意地操纵，以获得无法得到支持的身份认定概率，从而可能错误地呈现关联的不确定性。法医DNA领域需要制定客观计算先验概率的指导方针。
