School of Forensic Medicine, Shanxi Medical University, Jinzhong 030619, Shanxi, China.
Forensic Sci Int Genet. 2022 Jul;59:102703. doi: 10.1016/j.fsigen.2022.102703. Epub 2022 Apr 2.
In recent years, RNA profiling has become an important technique in identifying the origin of human body fluids/tissues. Both perpetrators and victims can be identified from stains involving vaginal secretions (VS), such as sperm/VS mixtures left on condoms, bed sheets, or papers, etc. Body fluid specific RNA typing could link the source of body fluids/tissues and the identity of the donor. In this study, we aimed to trace the donor of VS in mixture stains using body fluid-specific mRNA markers and construct a coding single nucleotide polymorphism (cSNP) typing system for VS. We screened 8 VS-specific mRNA biomarkers (MUC4, SFTA2, CYP2A6, MYOZ1, FUT6, ESR1, SPINK5, and SERPINB13) encompassing 18 cSNPs. The RNA obtained from various body fluid/tissue samples was treated with reverse transcription polymerase chain reaction (RT-PCR) and then followed by a multiplex PCR and SNaPshot mini-sequencing assay. The detection limit of the assay was 0.08 ng RNA. For single-source body fluid, the positive cSNP typing was only shown in VS and void in non-VS body fluids/tissues. For laboratory-generated VS-containing mixtures, the minor VS contributor could be successfully detected at a ratio of 1:10-1:500. We also confirmed the concordance of DNA typing and mRNA typing for the cSNPs in this system. In summary, we established an 18-cSNP typing system for VS with high sensitivity and specificity, which could identify both the donor and the tissue origin simultaneously. This was shown to be a powerful tool for identifying the VS donor in those VS-containing mixture stains.
近年来，RNA 谱分析已成为鉴定人体体液/组织来源的重要技术。无论是犯罪者还是受害者，都可以从涉及阴道分泌物（VS）的污渍中识别出来，例如避孕套、床单或纸张上留下的精液/VS 混合物等。体液特异性 RNA 分型可以将体液/组织的来源与供体的身份联系起来。在这项研究中，我们旨在使用体液特异性 mRNA 标记物追踪混合污渍中的 VS 供体，并构建 VS 的编码单核苷酸多态性（cSNP）分型系统。我们筛选了 8 种 VS 特异性 mRNA 生物标志物（MUC4、SFTA2、CYP2A6、MYOZ1、FUT6、ESR1、SPINK5 和 SERPINB13），涵盖 18 个 cSNP。从各种体液/组织样本中提取的 RNA 经过逆转录聚合酶链反应（RT-PCR）处理，然后进行多重 PCR 和 SNaPshot 迷你测序分析。该检测方法的检测限为 0.08 ng RNA。对于单源体液，仅在 VS 中显示阳性 cSNP 分型，而非 VS 体液/组织中则呈阴性。对于实验室生成的含有 VS 的混合物，较小的 VS 贡献者可以在 1:10-1:500 的比例下成功检测到。我们还确认了该系统中 cSNP 的 DNA 分型和 mRNA 分型的一致性。总之，我们建立了一种具有高灵敏度和特异性的 18-cSNP 分型系统，可同时鉴定供体和组织来源。这被证明是识别含有 VS 混合物污渍中 VS 供体的有力工具。
