Dawnay Nick, Ogden Rob, Thorpe Roger S, Pope Lisa C, Dawson Deborah A, McEwing Ross
School of Biological Sciences, University of Wales, Bangor LL57 2UW, United Kingdom.
Forensic Sci Int Genet. 2008 Jan;2(1):47-53. doi: 10.1016/j.fsigen.2007.08.006. Epub 2007 Sep 29.
Developing short tandem repeat (STR) profiling systems for forensic identification is complicated in animal species. Obtaining a representative number of individuals from populations, limited access to family groups and a lack of developed STR markers can make adhering to human forensic guidelines difficult. Furthermore, a lack of animal specific guidelines may explain why many wildlife forensic STR profiling systems developed to date have not appropriately addressed areas such as marker validation or the publication and analysis of population data necessary for the application of these tools to forensic science. Here we present a methodology used to develop an STR profiling system for a legally protected wildlife species, the Eurasian badger Meles meles. Ten previously isolated STR loci were selected based on their level of polymorphism, adherence to Hardy-Weinberg expectations and their fragment size. Each locus was individually validated with respect to its reproducibility, inheritance, species specificity, DNA template concentration and thermocycling parameters. The effects of chemical, substrate and environmental exposure were also investigated. All ten STR loci provided reliable and reproducible results, and optimal amplification conditions were defined. Allele frequencies from 20 representative populations in England and Wales are presented and used to calculate the level of population substructure (theta) and inbreeding (f). Accounting for these estimates, the average probability of identity (PI(ave)) was 2.18 x 10(-7). This case study can act as a framework for others attempting to develop wildlife forensic profiling systems.
为法医鉴定开发短串联重复序列（STR）分析系统在动物物种中较为复杂。从种群中获取具有代表性数量的个体、获取家族群体的机会有限以及缺乏已开发的STR标记，使得遵循人类法医指南变得困难。此外，缺乏针对动物的指南可能解释了为什么迄今为止许多开发的野生动物法医STR分析系统没有适当地解决标记验证或这些工具应用于法医学所需的种群数据的发布和分析等领域的问题。在此，我们展示了一种用于为一种受法律保护的野生动物物种——欧亚獾（Meles meles）开发STR分析系统的方法。根据其多态性水平、对哈迪-温伯格预期的符合情况及其片段大小，选择了10个先前分离的STR位点。每个位点都在其可重复性、遗传方式、物种特异性、DNA模板浓度和热循环参数方面进行了单独验证。还研究了化学、底物和环境暴露的影响。所有10个STR位点都提供了可靠且可重复的结果，并确定了最佳扩增条件。给出了来自英格兰和威尔士20个代表性种群的等位基因频率，并用于计算种群亚结构水平（theta）和近亲繁殖系数（f）。考虑到这些估计值，平均个体识别概率（PI(ave)）为2.18×10⁻⁷。本案例研究可为其他试图开发野生动物法医分析系统的人提供一个框架。
