体液斑的microRNA和DNA复合分析探索

One of the cutting-edge of forensic genetics is to identify the origin of the body fluid stains left at crime scene. It is important for understanding the nature of crime. The intrinsically short fragment and tissue-specific expression enable MicroRNA as a potential marker for the identification of body fluid stains with degraded or compromised samples frequently encountered in forensic casework. Our assumption is that there is a possibility of co-analysis of MicroRNA and DNA. The aims of this project are: 1) To clarify a group of MicroRNAs from that we find out there are different expression level among blood, saliva, semen and menstrual blood in order to provide new markers for the identification of body fluid stains. 2) To develop multiplex approach of simultaneously detecting different MicroRNAs to provide a promising new method for the identification of body fluid stains. 3) To explore MicroRNA and DNA co-analysis strategy and to provide a proof of concept in order to support the potential use of MicroRNA based system for the identification of body fluid stains in forensic casework that is compatible with current DNA analysis methodology.

法医物证学研究前沿之一是鉴定犯罪现场遗留的体液斑痕的组织来源，这对明确案件性质至关重要。小分子microRNA具有独特优势，适宜用于降解检材分析。我们提出鉴定体液斑的MicroRNA和DNA同步分析技术设想，同一斑痕由STR分型进行个人识别，由MicroRNA检测阐明组织来源。本课题目的在于：1)在我们用芯片找到的静脉血、唾液、精液和月经血表达有差异的MicroRNA中，阐明具有法医学鉴定意义的一组MicroRNA，为不同体液斑鉴定提供新的分子生物学标记。2) 探索复合检测多个MicroRNA的方法，为体液斑鉴定提供新的技术手段。3) 探索MicroRNA和DNA在法医自动激光荧光毛细管电泳平台上同步分析的可能性，完成科学设想的实验验证，以期建立MicroRNA和DNA同步分析技术，为法医生物学证据解释提供科学依据。

法医物证学研究前沿之一是鉴定犯罪现场遗留的体液斑痕的组织来源。小分子microRNA具有独特优势，适宜用于降解检材分析。本研究阐明了一组MicroRNA具有法医学意义。6个体液特异标记miRNAs分别适合用于法医血液(miR-16, miR-486, miR451a)、精液(miR888, miR891a)及月经血(miR214)鉴定；另发现miR-203a、miR-205和miR-200c在唾液具有相对高表达，为法医体液斑鉴定提供了新的分子生物学标记。我们成功地建立了MicroRNA/DNA共检测方法，利用线性逆转录引物、PCR特异性引物和PCR公共引物对多个目标MicroRNAs进行了逆转录和PCR扩增，通过毛细管电泳得到准确有效的分型结果。实现了同一个样本在毛细管电泳平台上同步分析MicroRNA和DNA，其中由STR分型进行个人识别，而MicroRNA鉴别其组织来源。为法医物证分析提供了新的科学手段。