CircRNAs标记在人类体液斑鉴定的法医学探索研究

In forensic casework, identification the cellular origin of a biological stains is important to the case investigation and reconstruction in crime scene. Recently, CircRNAs are revealed prevalently and abundantly expressed across life, featured stable structure and in a high tissue-and developmental stage-specific manner. Theoretically, circRNAs are more stable compared to linear RNAs owing to their higher nuclease stability, which show an enormous advantage from an application point of view as a novel class of biomarkers. In this study，we plan to screened the forensic body fluid-specific circRNAs by detecting expression profiles of human body fluids with circRNAs Arraystar Human circRNA Array, and looking for a set of possible and suitable circRNAs markers for forensic body fluids identification which satisfy the fluid specificity, more stable than linear RNA and have nothing to do with the disease. After validate these circRNAs sites by RT-qPCR approach, then the forward primers were 5’-labelled with fluorescent mark to developed a multiplex profiling system based on the endpoint PCR assay. Finally, we developed a strategy for co-extraction, co-analysis, co-detection of DNA /circRNAs from a material, which will be effective to solve the cases of body fluid and mixture samples.

在犯罪现场遗留的人体来源的体液及其斑痕可能是推定犯罪嫌疑人的有力证据。CircRNAs广泛存在于真核细胞中，具有物种间保守性、表达量较丰富以及一定的组织体液特异性，且其为闭合环状结构，对核酸外切酶不敏感，理论上比线性RNA更稳定，这使circRNAs在作为潜在新型法医体液鉴定标记物上更具优势。本课题拟采用circRNAs芯片技术对人类体液样本进行大规模初筛，寻找一组可能存在的符合法医学鉴定要求即具有体液特异性、比线性RNA更稳定且与疾病无关的circRNAs位点，通过实时荧光定量PCR技术验证后，探索复合检测多个circRNAs的方法，即对引物进行荧光标记，构建一个利用终点法PCR检测的复合荧光检测体系，使其能在毛细管电泳平台检测，并建立同一份体液斑进行circRNAs及DNA复合分析流程，为进行体液斑检材和混合斑检材鉴定提供有效的检测手段。

在犯罪现场遗留的人体来源的体液及其斑痕可能是推定犯罪嫌疑人的有力证据。在某些无法定性的案件中，对存留个体的生物学检材进行体液来源的鉴定是至关重要的。CircRNAs广泛存在于真核细胞中，存在组织特异性，且其为闭合环状结构，对核酸外切酶不敏感，是潜在的适用于环境变化复杂的生物检材的新型法医体液鉴定标记物。本课题基于circRNAs芯片技术，对中国汉族人群的血液、精液、唾液、阴道分泌液和月经血等5种体液样本进行检测分析，共找到12个circRNAs位点作为体液来源推断的标记，构建了自动激光荧光毛细管电泳分析体系。在中国汉族群体中，用本课题的筛选的circRNAs位点对现场血液、精液、唾液、阴道分泌液和月经血样本进行体液来源推断有较高准确性，为法医生物检材体液来源推断提供了新技术手段。