Institute of Legal Medicine, University Ulm, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
Institute of Legal Medicine, University Ulm, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
Forensic Sci Int Genet. 2021 Sep;54:102542. doi: 10.1016/j.fsigen.2021.102542. Epub 2021 May 29.
Molecular identification of body fluids and tissues is crucial in order to understand the circumstances of crimes. For that reason, molecular investigations used to identify body fluids/tissues have increasingly been examined recently. Various studies have proved that messenger RNA (mRNA) profiling is a sensitive and robust method for body fluid/tissue identification. The forensically relevant body fluids/tissues blood, semen, saliva, vaginal secretion, menstrual blood and skin have all been detected successfully by applying suitable mRNA assay. However, rectal mucosa, which can be found as evidence in sexual assault cases, has been neglected in forensic investigations. So far there is no mRNA marker to detect rectal mucosa, although anal penetration occurs in a large number of sexual assaults (23.2% of female victims and 50% of male victims). In this study, specific and sensitive mRNA markers for forensically relevant body fluids were adapted and validated in an mRNA multiplex assay for routine casework. This included the implementation of a DNA/RNA re-extraction method for automated extraction that can be integrated into casework without loss of DNA. This re-extraction method and the mRNA multiplex assay were tested using casework samples. PCR-primers were designed for the identification of rectal mucosa and the more effective marker MUC12 was integrated into an extended multiplex assay. The result of our study is a highly specific and sensitive mRNA multiplex assay plus an automated DNA/RNA re-extraction method, that can be integrated into casework and identify rectal mucosa for the first time.
为了了解犯罪情况，对体液和组织进行分子鉴定至关重要。因此，最近越来越多地对用于鉴定体液/组织的分子研究进行了检查。各种研究已经证明，信使 RNA（mRNA）分析是鉴定体液/组织的一种敏感且强大的方法。通过应用合适的 mRNA 检测方法，已经成功地检测到了法医相关的体液/组织，如血液、精液、唾液、阴道分泌物、月经血和皮肤。然而，在法医调查中，直肠黏膜作为性侵犯案件中的证据被忽视了。到目前为止，还没有用于检测直肠黏膜的 mRNA 标志物，尽管在大量性侵犯案件中都会发生肛门插入（女性受害者中有 23.2%，男性受害者中有 50%）。在这项研究中，适应并验证了用于法医相关体液的特异性和灵敏性 mRNA 标志物，并将其整合到用于常规案例工作的 mRNA 多重分析中。这包括实施一种用于自动化提取的 DNA/RNA 再提取方法，该方法可以在不损失 DNA 的情况下集成到案例工作中。该再提取方法和 mRNA 多重分析已在案例工作样本中进行了测试。设计了用于鉴定直肠黏膜的 PCR 引物，并将更有效的标志物 MUC12 整合到扩展的多重分析中。我们研究的结果是一种高度特异性和灵敏性的 mRNA 多重分析，加上一种自动化的 DNA/RNA 再提取方法，可首次集成到案例工作中并识别直肠黏膜。
