“Time of death?” . Forensic science has not yet been able to give a very exact answer to this topical question of films and crime series, although now it could refine more thanks to a new technique: the analysis of the necrobiome . Or put another way, the count of the community of bacteria that inhabits a corpse when it is found.
This will allow the so -called post-mortem interval (PMI) to be dated more accurately than with traditional clues, such as the state of the body and the insects that accompany it . Because weather conditions and geographic location often derail estimates.
To create their model, the researchers sequenced DNA from microbes collected from skin tissue from the nasal and ear canals of 21 cadavers at the University of Tennessee. Taking into account the changes in the microbial community, they assure, they can deduce the moment of death with a maximum error of two summer days , since the effects of time and temperature on the deterioration of the corpse are valued at the same time; From this point of view, one summer day is equivalent to two winter weeks.
“A decomposing vertebrate is like a very dynamic ecosystem ,” explained Nathan Lens, a microbiologist at the City University of New York and lead author of the study. There are biological factors, such as the decrease in oxygen and nutrient levels , that significantly vary the type of microorganisms that colonize the body. The researchers, who have just published their work in the journal PLOS ONE , believe that in the future they will be able to expand the areas where the samples are taken and make even more reliable models .
Photo: WorldSkills UK / Flickr
