DNA Methylation and Epigenomic Profiling Post-Mortem of Human Remain Analogs (Sus Scrofa) in Southern Ontario, Canada

Abstract

Understanding the dynamics of DNA methylation (DNAm) post-mortem is crucial for advancing forensic applications, particularly in estimating the post-mortem interval (PMI), age, and sex of remains. In this study we investigated DNAm changes in pig carcasses (Sus scrofa) as analogs for human decomposition, while measuring the progression of decay. Overall, DNA integrity and DNAm levels declined throughout the post-mortem period. We established thresholds for estimating age and sex post-mortem, referred to as epigenomic profiling, showing that key epigenetic markers retain predictive value post-mortem. These thresholds varied by season and according to the epigenetic clock utilized. Additionally, we developed an ElasticNet model that integrates DNAm to estimate the PMI, highlighting the potential of DNAm as an investigative tool.

Keywords: Forensic epigenetics, forensic taphonomy, decomposition, PMI estimation, Pig, Dfb climate