Detection of microRNAs in DNA Extractions for Forensic Biological Source Identification

Abstract Molecular‐based approaches for biological source identification are of great interest in the forensic community because of a lack of sensitivity and specificity in current methods. Micro RNA s (mi RNA s) have been considered due to their robust nature and tissue specificity; however, analysis requires a separate RNA extraction, requiring an additional step in the forensic analysis workflow. The purpose of this study was to evaluate mi RNA detection in blood, semen, and saliva using DNA extraction methods commonly utilized for forensic casework. RT ‐ qPCR analysis revealed that the tested mi RNA s were consistently detectable across most tested DNA extraction methods, but detection was significantly reduced compared to RNA extracts in some biological fluids. DN ase treatment was not necessary to achieve mi RNA ‐specific results. A previously developed mi RNA panel for forensic body fluid identification was evaluated using DNA extracts, and largely demonstrated concordance with results from samples deriving from RNA extracts of semen, blood, and saliva.