The postmortem microbiome is an emerging field in forensic science with broad application for death investigation (e.g., time since death). While the foundation for forensic microbiology began in the early 2000s, resulting from bioterrorism threats, the expansion of using entire microbial communities (the microbial organisms, their genes, and their gene functions) in a forensic context began in the early 2010s. Improvements in molecular approaches over the past twenty years to study the microbiome in medical fields have revealed the power and potential use of microbial diversity as a means to explore the associations of microorganisms with human health of living individuals. Researchers within forensic sciences adopted these technologies to determine if and how the postmortem microbiome could be used to aid death investigation. The importance of the human microbiome and its function in health during life is well known. However, few studies characterize the dynamics of the postmortem human microbiota from samples collected during real-world death investigation. Here, we discuss the on-going results from an extensive database of microbial samples with a focus on a major metropolitan urban city. Microbial taxonomic profiles from routine death investigation cases were generated through targeted amplicon sequencing (16S rRNA). The goal of this project is to provide a robust dataset of postmortem microbial communities. In the future, these data will advance death investigation by identifying specific microbial taxa or signatures of importance for application in forensic sciences and beyond.

Learning Objectives:

1. Define and discuss the variability of human microbiomes after death, as determined from samples collected during routine death investigation.

2. Use bioinformatic tools to identify potential signatures of postmortem microbiomes associated with circumstances of death.

3. Discuss the future of postmortem microbiomes in forensic sciences and other applied sciences, such as public health.