Defense Date

2021

Document Type

Thesis

First Advisor

Dr. Sarah Seashols-Williams

Second Advisor

Dr.Tracey Dawson Green

Third Advisor

Dr. Edward Boone

Abstract

Abstract

In forensic investigations, body fluids can provide crucial information and is helpful for corroborating the circumstance of the case. For cases of sexual assaults or homicides, being able to differentiate if the blood is peripheral blood or menstrual blood is important. Peripheral blood can be indicative of a traumatic event, while menstrual blood is of a natural cause. Currently, serology based methods are used for body fluid identification, however, their lack of sensitivity and specificity remains an issue. MicroRNAs (miRNAs) are a class of non-protein coding nucleic acids that are able to be co-extracted with DNA, and their small size (18-25 nucleotides) makes them ideal for analyzing highly degraded forensic samples. This study used RT-qPCR to evaluate the relative expression of candidate miRNAs miR-141 and miR-412, for their ability to distinguish between menstrual and peripheral blood and to further enhance a previously validated miRNA panel consisting of miR-200b, miR-891a, miR-10b, and miR-320. A population size of 50 samples of peripheral blood, menstrual blood, feces, semen, urine, saliva, and vaginal fluid were tested. A quadratic discriminant analysis matrix was used to facilitate the classification of unknown body fluids using miRNA expression data. Our results established that using miR-141 and miR-412 in conjunction with the previously validated panel allow for a prediction accuracy of 91.36%, an increase of 3.36% over prediction accuracy without miRs 141 and 412. Overall, the relative expression of miRNAs in body fluids is promising as a method of body fluid identification with potential to be developed into a multiplex that could be easily integrated into forensic crime laboratories.

Keywords: forensic science, forensic serology, body fluid identification, microRNA, menstrual blood, reverse transcription-quantitative polymerase chain reaction

Rights

© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

5-4-2021

Share

COinS