A biomarker for age estimation in forensic medecine: Analysis of age and sex-dependent miR-766-3p expression levels in Saliva

A Biomarker for Age Estimation in Forensic Medicine: Analysis of Age and Sex-Dependent Expression Levels of MiR-766-3p in Saliva Determining a person of interest's age in routine forensic cases can be a pivotal lead to an investigation, however, this task remains challenging. Beyond the forensic scope, age prediction tools could be an asset to several other fields including immigration, anthropology and disaster victim identification programs. Several leads have been explored to understand the complex underpinnings of ageing to create an effective prediction model. Initially known for their role in histone deacetylation, sirtuins (SIRTs) have received growing attention, regarding their role in ageing and age-related diseases as SIRT6 shows a downregulation with ageing. The question of "What factors affect SIRT6 expression?" would, therefore, be valid, when trying to elucidate the complex network involved in ageing and when designing age prediction models. MicroRNAs known for their role in gene silencing are one such factor. MiR-766-3p targets the SIRT6 via a feedback regulatory loop. The analysis of the expression patterns of miR-766-3p in the saliva samples of different age groups may give more insight into miRNA-age-related circuitry and determine its potential as a candidate biomarker for age prediction tools. Our results show a difference in the expression patterns of women and men. Where women show an upregulation, men show a downregulation with age. Keywords: Aging, Senescence, Biomarker, Saliva, SIRT6, MiR-766-3p, Chronological age estimation, Forensic Sciences, RNA extraction, RT-PCR; Real-Time, Polymerase Chain Reaction