Could the salivary microbiota be an individual signature?

Abstract

DNA is one of the important pieces of evidence at the crime scene. There may be cases where the DNA is damaged or insufficient. In this case, the criminal can be identified by qualifying microorganisms as evidence. In recent studies, it has been shown that the detection of microbiota communities on the surface of the human body can bring a new perspective to forensic science. In our study, we investigated the importance of the microbiota in the saliva in terms of identification in forensic sciences, by using phenotypic and morphological features as opposed to genotypic identification, and by checking how unique and characteristic features of these determined microorganisms are compared to other people. 60 different swab samples, including the mouth and bitten right index finger, were cultivated in 4 different media (Blood, Chocolate, Endo, and Chrom) from 30 subjects. All reproducible microorganisms found in the saliva of individuals were investigated. According to the data obtained from the mouth and bitten finger; It was determined that alpha-hemolytic streptococci were the most dominant species among these microorganisms. In addition, Neisseria sp bacteria in the salivary microbiota of individuals have been shown to have a significant relationship with smoking and Candida sp with oral hygiene. We believe that this study will present a different perspective to the literature in cases where the DNA procedure obtained from the bite marks of suspects in the criminal investigation is degraded or insufficient, or to obtain a complementary result in addition to genotypic approaches.