"Forens-OMICS": a cross disciplinary implementation of omics sciences to in vivo and post-mortem ageing investigations for forensic applications

这一研究项目的目的是应用现代生物学和生物化学实验室中现有的一些最尖端的技术来解决法医为了解决犯罪而可能被要求回答的两个最重要的问题，即受害者的死后间隔(PMI)(从他/她死亡起经过的时间)和受害者的年龄(AAD，死亡年龄)。尽管有几种不同的方法可以用来进行这些估计，但它们通常依赖进行分析的法医科学家的专业知识，因此个体间的重复性和客观性很差。此外，迄今为止开发的大多数估计PMI的技术都依赖于必须对软组织进行的评估(例如，在死亡后很短的一段时间内)，而旨在解决AAD的技术往往依赖于骨骼的完整性来寻找特定的形态骨骼特征(例如，颅缝、耻骨联合)，这些特征可以提供关于受害者年龄的信息。从这些假设出发，实际方法的局限性是显而易见的，即缺乏从骨骼遗骸或不完整身体(如身体碎片)中获得的老化信息，这对于悬案受害者、自然灾害、战争受害者、恐怖袭击、人口贩运受害者以及考古挖掘来说是非常常见的情况。如今，技术进步使研究人员能够从非常少量的材料开始提取宝贵的生物信息，例如非常小的骨骼碎片。这包括遗传信息以及蛋白质和代谢物信息，这些信息通常被概括为“组学”学科的通用术语。有趣的是，这里引用的所有生物分子都可以根据包含它们的生物组织的体内和死后老化现象带来特定的“签名”，这些签名可以在一个小的生物样本中以非靶标的方式进行研究，以评估它们与衰老现象(PMI和AAD)的联系及其预测能力。术语“Forens-OMICS”在这里指的是若干“组学”技术的首次全球应用，这些技术旨在主要用于法医应用，但也用于考古。为了实现这些目标，与美利坚合众国的几个人类学机构新建立的几项合作将允许收集和采样大量的人骨，这些人的骨骼既有年龄范围很广的个人(从非常年轻的人到老年人)，也有具有广泛的个人特征的个人(从几个月到40多岁)。然后，收集的骨骼样本将用于提取DNA、蛋白质和代谢物，并将对这些特定生物分子中的每一个进行高通量分析，以推断与PMI和AAD相关的可量化特征。然后，所有恢复的信息将与先进的生物信息学工具结合在一起，以开发一个数学模型，估计PMI和AAD，并预测方法的预测能力，以及澄清哪种生物分子(或其组合)将提供最准确的估计。总之，新发现的生物标志物将被用于开发一种商业试剂盒，可供法医、警察或研究人员使用，以简单、快速、公正和可靠的方式做出这些评估。该工具包还将允许“非组学”专家获得基本的调查线索，这些线索将有助于改善未侦破犯罪的结果，以及未来涉及骨架或高度碎片化遗骸的犯罪的结果。

The aim of this research project is to apply some of the most cutting-edge technologies available in modern biology and biochemistry laboratories to address two of the most important questions that a forensic scientist could be asked to answer in order to solve a crime, namely the post-mortem interval (PMI) of the victim (the time elapsed from his/her death) and the age of the victim (AAD, age-at-death). Despite the availability of several different approaches that can be used to perform these estimations, they usually rely on the expertise of the forensic scientist that performs the analysis, thus suffering from poor inter-individual reproducibility and objectivity. Moreover, most of the techniques developed so far to estimate PMI rely on evaluations that has to be performed on soft tissues (e.g. after short periods from death), and techniques aimed at addressing AAD often rely on the completeness of the skeleton to look for specific morphological skeletal traits (e.g., cranial sutures, pubic symphysis) that can give information about the chronological age of the victim. Starting from these assumptions, it is clear and evident what the limits of the actual methodologies are, that is the lack of ageing information obtainable from skeletonised remains or from incomplete bodies (such as body fragments), which is a very common situation for cold cases victims, natural disasters, war victims, terroristic attacks, human trafficking victims, and also for archaeological excavations.Nowadays, technological progress allows researchers to extract an invaluable amount of biological information starting from very small amount of materials such as very small fragment of bone. This includes genetic information, as well as protein and metabolite information, and these are generally summarised under the common term of "omics" disciplines. Interestingly, all the biomolecules cited here can bring a specific "signature" depending on in-vivo and post-mortem ageing phenomena of the biological tissue that contains them, and these signatures could be investigated within a small biological sample in a non-targeted way, in order to evaluate their linkage with ageing phenomena (both PMI and AAD) and their predictive power. The term "Forens-OMICS" indicates here the first global application of several "omics" technologies aimed to address ageing phenomena primarily for forensic applications, but also for archaeological ones.To achieve these aims, several newly established collaborations with several anthropological facilities in the United States of America will allow the collection and the sampling of a significant number of human bones of either individuals with a wide age range (from very young to elderly individuals) and of individuals characterised by a wide range of PMIs (from a couple of months to over forty years). The bone samples collected will be then used to extract DNA, proteins and metabolites, and high-throughput analyses will be performed on each of these specific biomolecules to extrapolate quantifiable features associated with both PMI and AAD. All the recovered information will then be combined together with advanced bioinformatics tools, in order to develop a mathematical model that will estimate PMI and AAD, and that will predict the predictive power of the methodology, as well as clarifying which of the biomolecules (or combination thereof) will provide the most accurate estimations. To conclude, the newly found biomarkers will be used to develop a commercial kit that could be used by forensic examiners, police officers or researchers to make these estimations in an easy, quick, un-biased and reliable way. The kit will also allow "non-omics" experts to get fundamental investigative clues that will help to improve the outcome of unsolved crimes and of future crimes involving the presence of skeletonised or highly fragmented remains.