MicroRNA markers for forensic body fluid identification obtained from miRCURY™ LNA array

Abstract

MicroRNA is a promising marker for forensic body identification especially in compromised samples and mixtures because of its small size and tissue specific expression manner. Previously, five research groups have reported specific miRNAs screened from different arrays for body fluid identification. Our study aims to screen appropriate miRNAs for forensic body fluid identification through Exiqon’s miRCURY™ LNA Array. Five samples of six common body fluids were collected including peripheral blood, menstrual blood (six samples for menstrual blood), saliva, semen, vaginal secretion and skin swabs. Eight novel miRNAs and two reported markers were selected to identify five commom body fluids. Reliable miRNA markers for skin cells couldn’t be identified because relative expression ratios from array results were not large enough to identify target body fluid. Our result suggest that, maybe more markers should be combined together to identify the skin cells, and the strategy need to be refined. Our study first introduces skin cells into the microarray screening and enriches the candidates for forensic body fluid identification.