Researchi̇ng the avai̇labi̇li̇ty of the speci̇fi̇c MRNA markers for body flui̇d i̇denti̇fi̇cati̇on

MRNA expression differs among cell types; because of this characteristic it's asserted that mRNAs can be used in order to identify the body fluids in forensic samples. The aim of this study is to search the usability of a series of mRNA markers' chosen for blood, menstrual blood, semen and vaginal secretion in identification of body fluids. For this purpose, Hemoglobin Beta (HBB), Glycophorin A (GYPA) for blood, Kallikrein 3 (KLK3), Semenogelin (SEM1) for semen, Matrix Metalloproteinase 10 (MMP10) for menstrual blood and bacteria RNAs of Lactobacillus gasseri (Lgas), Lactobacillus crispatus (Lcris) and Lactobacillus jensenii (Ljen) for vaginal secretion were chosen. Transcription elongation factor SII (TEF) and E2 ubiquitin-conjugating enzyme UbcH5b (UCE) were used as endogenous control genes. Following the application of RNA isolation (RNA/DNA/miRNA isolation kit), cDNA syntheses (Superscript vilo cDNA syntheses kit), single- and multiplex-PCR methods on experimentally prepared blood, menstrual blood, semen and vaginal secretion stains, PCR products were run on automatic capillary electrophoresis. All mRNA markers used in this study were found in target body fluids. Besides, while blood markers HBB and GYPA present in all menstrual blood samples because of their nature, menstrual blood marker MMP10 wasn't identified in whole blood samples. Also, Lgas marker which has to be found in vaginal secretion was identified in menstrual blood. Semen and menstrual blood markers were found specific in related body fluid. Chosen markers for blood, menstrual blood, semen and vaginal secretion were able to be shown on 6-months-old stains which were experimentally prepared and stored at different environment conditions. Also, it's sought that the stability of mRNA markers' which were HBB for blood stains, SEM for semen stains stored for 5 years in different environments was considerably high. After all the experimental studies which made in order to analyze all markers simultaneously, all markers were included in the multiplex system and 10-plex assay could be produced. With the obtained findings, it was concluded that the chosen markers for blood, menstrual blood, semen and vaginal secretion could be used in the identification of target body fluids, and also the topic of whether the stains belong to the target body fluids with the multiplex amplification could be answered at once. Key words: mRNA, body fluid identification, mRNA markers, forensic.