Walsh Susan, Chaitanya Lakshmi, Clarisse Lindy, Wirken Laura, Draus-Barini Jolanta, Kovatsi Leda, Maeda Hitoshi, Ishikawa Takaki, Sijen Titia, de Knijff Peter, Branicki Wojciech, Liu Fan, Kayser Manfred
Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
Department of Human Biological Traces, Netherlands Forensic Institute, The Hague, The Netherlands.
Forensic Sci Int Genet. 2014 Mar;9:150-61. doi: 10.1016/j.fsigen.2013.12.006. Epub 2013 Dec 27.
Forensic DNA Phenotyping or 'DNA intelligence' tools are expected to aid police investigations and find unknown individuals by providing information on externally visible characteristics of unknown suspects, perpetrators and missing persons from biological samples. This is especially useful in cases where conventional DNA profiling or other means remain non-informative. Recently, we introduced the HIrisPlex system, capable of predicting both eye and hair colour from DNA. In the present developmental validation study, we demonstrate that the HIrisPlex assay performs in full agreement with the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines providing an essential prerequisite for future HIrisPlex applications to forensic casework. The HIrisPlex assay produces complete profiles down to only 63 pg of DNA. Species testing revealed human specificity for a complete HIrisPlex profile, while only non-human primates showed the closest full profile at 20 out of the 24 DNA markers, in all animals tested. Rigorous testing of simulated forensic casework samples such as blood, semen, saliva stains, hairs with roots as well as extremely low quantity touch (trace) DNA samples, produced complete profiles in 88% of cases. Concordance testing performed between five independent forensic laboratories displayed consistent reproducible results on varying types of DNA samples. Due to its design, the assay caters for degraded samples, underlined here by results from artificially degraded DNA and from simulated casework samples of degraded DNA. This aspect was also demonstrated previously on DNA samples from human remains up to several hundreds of years old. With this paper, we also introduce enhanced eye and hair colour prediction models based on enlarged underlying databases of HIrisPlex genotypes and eye/hair colour phenotypes (eye colour: N = 9188 and hair colour: N = 1601). Furthermore, we present an online web-based system for individual eye and hair colour prediction from full and partial HIrisPlex DNA profiles. By demonstrating that the HIrisPlex assay is fully compatible with the SWGDAM guidelines, we provide the first forensically validated DNA test system for parallel eye and hair colour prediction now available to forensic laboratories for immediate casework application, including missing person cases. Given the robustness and sensitivity described here and in previous work, the HIrisPlex system is also suitable for analysing old and ancient DNA in anthropological and evolutionary studies.
法医DNA表型分析或“DNA情报”工具有望通过从生物样本中提供未知嫌疑人、犯罪者和失踪人员的外部可见特征信息来协助警方调查并找到未知个体。这在传统DNA分析或其他方法仍无信息价值的案件中尤其有用。最近，我们推出了HIrisPlex系统，能够从DNA预测眼睛和头发颜色。在当前的开发验证研究中，我们证明HIrisPlex检测完全符合DNA分析方法科学工作组（SWGDAM）的指南，为未来HIrisPlex应用于法医案件工作提供了必要前提。HIrisPlex检测仅需63 pg的DNA就能生成完整图谱。物种检测显示完整的HIrisPlex图谱具有人类特异性，而在所有测试动物中，只有非人类灵长类动物在24个DNA标记中的20个上显示出最接近的完整图谱。对模拟法医案件样本如血液、精液、唾液斑、带根毛发以及极低量的触摸（微量）DNA样本进行的严格测试，在88%的案例中生成了完整图谱。在五个独立的法医实验室之间进行的一致性测试在不同类型的DNA样本上显示出一致的可重复结果。由于其设计，该检测适用于降解样本，人工降解DNA和模拟降解DNA案件样本的结果突出了这一点。这一方面此前也在距今数百年的人类遗骸的DNA样本上得到了证明。在本文中，我们还基于扩大的HIrisPlex基因型和眼睛/头发颜色表型基础数据库（眼睛颜色：N = 9188，头发颜色：N = 1601）引入了增强的眼睛和头发颜色预测模型。此外，我们还展示了一个基于网络的在线系统，用于根据完整和部分HIrisPlex DNA图谱预测个体的眼睛和头发颜色。通过证明HIrisPlex检测与SWGDAM指南完全兼容，我们提供了首个经过法医验证的用于同时预测眼睛和头发颜色的DNA检测系统，现在法医实验室可将其立即应用于案件工作，包括失踪人员案件。鉴于本文及先前工作中所描述的稳健性和敏感性，HIrisPlex系统也适用于人类学和进化研究中的古代和古老DNA分析。
