A Molecular Method to Correlate Bloodstains with Wound Site for Crime Scene Reconstruction

Bloodstain pattern analysis to determine the wound‐of‐origin of bloodstains is problematic with nonspecific patterns. In this proof‐of‐concept study, the authors examined a molecular approach to correlate bloodstains with injuries using the rat as a model. Specifically, investigations were conducted on the rat brain marker, rno‐miR‐124‐3p, with the QIAGEN miScript System and real‐time PCR analysis. Rno‐miR‐124‐3p was detected in brain homogenates diluted 100,000 times; in 3‐week‐old, room temperature stored, simulated brain–blood stains; and in bloodstains from head gunshot wounds collected with swabs and subsequently frozen for 9–18 months; however, rno‐miR‐124‐3p was not detected in whole blood. Proof‐of‐principle was demonstrated by the ability to distinguish bloodstains from a gunshot wound to the head versus bloodstains from a gunshot wound to the chest, by the testing of otherwise identical bloodstains from the two patterns for the presence of the marker. The results suggest a viable approach to a longstanding problem in casework.