title: Assessing the suitability of miRNA-142-5p and miRNA-541 for bloodstain deposition timing.
abstract: A recent proof-of-concept pilot study proposed using microRNA (miRNA) markers for time of death determination. The markers - miRNA-142-5p and miRNA-541, were reported to show considerable expression differences in vitreous humor between individuals who died during the day or night. Here, we investigated whether these miRNA markers show the same diurnal expression pattern in blood, which would make them useful for estimating bloodstain deposition time to allow molecular alibi testing for forensic casework. We analyzed venous blood samples collected from 12 healthy individuals every 4h during the 24hday/night period under controlled sleep-laboratory conditions. MiRNA-142-5p normalized against miRNA-222 showed no statistically significant expression differences between blood samples collected during daytime and nighttime (one-way ANOVA p=0.81), and also no statistically significant rhythmicity during the 24hday/night period (cosine fit for all individuals p>0.05, averaged data p=0.932). MicroRNA-541 amplification in blood was above the 34-cycle threshold applied in the study, indicating too low quantities for obtaining reliable data. Overall, we conclude that the two miRNA markers previously suggested for time of death determination in vitreous humor are not suitable for estimating the deposition time of forensic bloodstains. Future studies may find out if miRNA markers with significant diurnal expression patterns can be identified and how useful they would be for forensic trace deposition timing.
authors.affiliation: Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Karolina
authors.initials: K
authors.lastname: Lech
authors.affiliation: Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Katrin
authors.initials: K
authors.lastname: Ackermann
authors.affiliation: Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wollstein
authors.affiliation: Centre for Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, UK.
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Revell
authors.affiliation: Centre for Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, UK.
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Skene
authors.affiliation: Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands. Electronic address: m.kayser@erasmusmc.nl.
authors.forename: Manfred
authors.initials: M
authors.lastname: Kayser
mesh_terms: D053803:Forensic Genetics; D005819:Genetic Markers; D035683:MicroRNAs / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D005819:Genetic Markers; C555159:MIRN142 microRNA, human; C000596382:MIRN541 microRNA, human; D035683:MicroRNAs
keywords: Biomarkers; Circadian; MicroRNA; Trace timing