Specific Micro‐RNA Signatures for the Detection of Saliva and Blood in Forensic Body‐fluid Identification

Abstract

Micro‐RNAs (miRNAs) are a class of small noncoding RNA (ncRNA) molecules with a length of 18–24 nucleotides which play an essential regulative role for many cellular processes. Evidence suggests that the miRNome is a more precise and meaningful representation of a cell type and condition than the mRNA transcriptome. To identify miRNAs that are suitable for forensic body‐fluid identification, a global screening by microarray analysis of c. 800 miRNAs of forensic blood and saliva samples was performed, and by bioinformatic processing, three differentially expressed candidate miRNAs for saliva and blood each were selected. The six candidates were then validated and confirmed via quantitative PCR. Herein, we present miRNA assays consisting of three differentially expressed miRNAs for the identification of blood (miR‐126, miR‐150, miR‐451) and saliva (miR‐200c, miR‐203, miR‐205), respectively. We conclude that miRNA extraction from forensic samples is possible and support a “proof of concept” that body‐fluid identification by miRNA analysis may become a potent forensic technique.

Small RNA Transcriptomes of Two Types of Exosomes in Human Whole Saliva Determined by Next Generation Sequencing

“…There are some reports that have used microarrays and/or quantitative polymerase chain reaction (PCR) to investigate the miRNA transcriptome of saliva. [24][25][26][27] As probes in these methodologies are designed on the basis of gene annotation, these analyses were limited to known miRNAs, and little information was gained regarding other small RNAs or novel RNAs.…”

Next generation sequencing (NGS): a golden tool in forensic toolkit

“…Dojrzałe miRNA charakteryzują się większą stabilnością niż mRNA, co ma istotne znaczenie dla badań kryminalistycznych. Umożliwia to odzysk miRNA ze skrawków tkanek utrwalonych w bloczkach parafinowych (FFPE) i jest skuteczniejsze od profilowania ekspresji mRNA z wykorzystaniem tkanek FFPE [18].…”

“…Mature miRNAs are more stable than mRNAs which is important in forensic investigations. Thus, the miR-NA recovery from formalin-fixed paraffin-embedded (FFPE) tissues is possible and it is better than FFPE tissue mRNA expression profiling [18].…”

Quantitative Analyses of Postmortem Heat Shock Protein mRNA Profiles in the Occipital Lobes of Human Cerebral Cortices: Implications in Cause of Death

“…For instance, postmortem profiles of several mRNA species, such as immediate early genes, hypoxia-inducible factor-1α, erythropoietin, vascular endothelial growth factor, glucose transporter-1, surfactants, and dual-specificity phosphatase 1, have been proposed to be related to certain causes and circumstances of death (Ikematsu et al, 2005;Miyazato et al, 2012;Takahashi et al, 2009;Zhao et al, 2006;. However, in contrast to the identification of body fluids and tissues using nucleic acid biomarkers (Courts and Madea, 2011;Haas et al, 2009;Juusola and Ballantyne, 2003;Zubakov et al, 2008;, the application of molecular pathological examination based on postmortem gene expression profiles to death processes appears to be still challenging. Despite technical advances in resolving the difficulties of sensitivity and standardization (Catts, 2005;Heinrich et al, 2007b;Lee et al, 2005), there remain limitations primarily due to the restricted understanding of molecular physiology at the time of death and, subsequently, the insufficiency of well-established forensic RNA biomarkers.…”