Thanatomicrobiome and postmortem microbial succession: ecological dynamics, molecular advances, and emerging forensic applications

The human body harbors a vast and diverse community of microorganisms that play essential roles in maintaining host health during life. After death, this complex microbial ecosystem undergoes dynamic transformations as endogenous and exogenous microbes interact within the nutrient-rich cadaveric environment. These changes, collectively referred to as the thanatomicrobiome (microorganisms inhabiting internal organs and body fluids after death) and the epinecrotic community (microorganisms colonizing body surfaces), provide valuable insights into postmortem processes. Advances in molecular techniques, including metagenomics, 16S rRNA, ITS, and 18S rDNA sequencing, have significantly improved the identification and characterization of postmortem microbial communities. These approaches not only enhance the accuracy of postmortem interval (PMI) estimation but also expand forensic applications. Microbial signatures can contribute to determining the cause and circumstances of death, estimating geolocation, and providing microbial trace evidence that links individuals or objects to specific environments. Additionally, the study of the necrobiome, encompassing microbial communities within and surrounding decomposing remains, offers insights into decomposition dynamics and environmental interactions. Despite these advances, the routine forensic application of microbial evidence remains limited due to methodological variability, lack of standardized protocols, and insufficient reference datasets. Continued integration of multi-omics approaches, along with bioinformatics and artificial intelligence, is expected to improve the reliability and applicability of microbial-based forensic tools in modern criminal investigations.