“These skeletons may have been out in the field for one year, three years, or various time periods,” Dr. Sheree Hughes, the director of the Southeast Texas Applied Forensic Science Facility (STAFS), said.
At this facility – part of Sam Houston State University – researchers use bodies donated by families to advance forensic science, looking at factors surrounding decomposition and death. There are only eight body labs like this throughout the U.S.
But figuring out an accurate time of death on skeletal remains has been a struggle in many cases. Now, that could be changing.
“At the moment, there is no reliable method to be able to determine time since the death of bones,” Hughes said. “After that time, when all the soft tissues have decomposed and have gone, all we’re left with is the skeletal remains and the bones there. They don't decompose in a very predictable pattern.”
Investigators use DNA to help solve that puzzle, but even DNA can be damaged after a while, so researchers like Noemi Procopio have turned to other indicators. Her research is primarily being conducted in the UK, but she is working on the study with Hughes and other body labs.
“We are looking at biomolecules in bones such as DNA, proteins, lipids, and metabolites,” Dr. Noemi Procopio, a senior research fellow at Northumbria University, Newcastle, said. She is also a UKRI Future Leaders Fellow, which provided the funding. “When you put together all these results, you can then try to develop methods to estimate either the chronological age or the postmortem interval by combining multiple omics together.”
The researchers are looking at biomolecules inside bones for post-mortem-interval and age-at-death estimation.
“Our role here in Noemi’s research is providing her the skeletal samples she needs for her project,” Hughes said.
This is how it works. Bone samples from a range of skeletons are sent from the body lab to Procopio’s lab in England. After promising results from animal bones, Procopio was able to start research on human bones.
“So far, I’ve sampled over 100 different portions of bones,” Procopio said. Her team takes fragments of the bones sent to their lab and uses technology and machines to separate each biomolecule.
“The next step in the study will be combining them together to see if they can help feed information one into another one, to get better estimations,” she said. “Any kind of improvement in the way in which we can get an estimation will be a massive achievement.”
An estimated 4,400 unidentified bodies are recovered each year in the U.S. Approximately 1,000 of those bodies remain unidentified after one year, according to the National Missing and Unidentified Persons System statistics.
“Having a precise estimation of the age of the person and understanding exactly when that person died can be extremely beneficial for getting information on missing individuals and unidentified remains,” Procopio said.
“It’s really exciting because it’s a piece of the puzzle that we don't have,” Hughes said.
Procopio’s team has a few more years of research ahead, but the results look promising.
“The end goal is to solve more cases. Be able to identify more missing persons, identify skeletons, be able to provide investigators with information they didn't have, so we can solve more cases and bring closure to more families,” Hughes said.