Bacteria surround us everywhere we go. They inhabit every corner of our world, from the places we work and live to the insides of our own bodies. They play an enormous role in our health and well-being, from the development of disease and allergies to how we respond to medicine—and they have the final say in death as well.
Jack Gilbert, faculty director of the Microbiome Center at the University of Chicago, and Gulnaz Javan, a forensic scientist from Alabama State University, received a two-year, $532,000 grant from the National Institute of Justice to study the thanatomicrobiome, or “microbiome of death.” The term was coined by Javan to describe the collection of microbes from internal organs collected during criminal casework. The project will develop tools to help determine the time and cause of death by identifying patterns of bacterial growth in a corpse's internal organs after death.
Previous work by Gilbert in 2016 showed how bacteria can help pinpoint the time and place of death, but he and Javan also want to see how stress on the body at the time of death leaves a unique signature on microbiota in the organs. The team will work with cadavers from national morgues in Montgomery, Ala., and Pensacola, Fla., plus an international morgue in Tampere, Finland, the largest morgue in that country. They will also explore relationships with morgues in Italy to increase the size and diversity of human corpses and organs that can be studied.
“The aim of this study is to determine whether we can calculate the time of death based on the bacteria that have escaped their normal body habitats and invaded internal organs” Gilbert said. “Once the body dies, the immune system fails and your microbiome is set free – we can track how the microbes migrate by examining the organs of hundreds of bodies.”
The team also hopes to determine if the microbial signature of the organs has any predictive ability when it comes to determining how the individual died.
“We have samples from natural deaths through murders, and we expect to be able to find a signature of how the person died based on the specific bacteria that colonize the organs first,” Gilbert said.
The study will run from January 2018 through December 2019.