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microRNA Detection in Blood, Urine, Semen, and Saliva Stains After Compromising Treatments

NCJ Number
Journal of Forensic Sciences Volume: 64 Issue: 6 Dated: 2019 Pages: 1831-1837
Date Published
7 pages

This article presents the findings and methodology of a study that involved the use of microRNA to detect blood, urine, semen, and saliva stains after compromising treatments.


Evaluation of microRNA (miRNA) expression as a potential method for forensic body fluid identification has been the subject of investigation over the past several years. Because of their size and encapsulation within proteins and lipids, miRNAs are inherently less susceptible to degradation than other RNAs. In this work, blood, urine, semen, and saliva were exposed to environmental and chemical conditions mimicking sample compromise at the crime scene. For many treated samples, including 100% of blood samples, miRNAs remained detectable, comparable to the untreated control. Sample degradation varied by body fluid and treatment, with blood remarkably resistant, while semen and saliva are more susceptible to environmental insult. Body fluid identification using relative miRNA expression of blood and semen of the exposed samples was 100 percent and 94 percent, respectively. Given the overall robust results herein, the case is strengthened for the use of miRNAs as a molecular method for body fluid identification. (publisher abstract modified)

Date Published: January 1, 2019