Blood and Saliva Identification through miRNA in Forensic Molecular Biology

Abstract

A class of non-coding miRNAs has attracted a lot of interest in the field of forensic sciences. miRNA has a relatively small size thus it is quite stable to the external environmental pressures and factors, which makes it very useful in forensic examination when used as a bio marker. At present, many of the specific miRNAs of body fluids can be distinguished by measuring their level of expression. Fresh blood samples and saliva samples were taken from 3 males and 3 females. RNA was extracted using TRIzol method and cDNA synthesis was done. RT reactions were made using SYBR Green master mix for RT-qPCR for quantification and detection of miRNAs. The designed primers were runs against the sample in qPCR and result was seen and compiled. Two miRNA were detected and expressed in both blood and saliva but they failed to differentiate between blood and saliva due to the non-specific primer binding according the methodology used in this study. Hsa-miR20a and Hsa-miR583 have been found to be non-specific for the blood and saliva. No stark difference could be observed on the basis of which we can say that Hsa-miR20a and HsamiR583 were specific for blood and saliva due to non-specific primer binding. Further research work is required in this domain of body fluids identification and differentiation using miRNA markers.