Police investigators recently uncovered a body in Mexico that was so badly burned and unrecognizable that even its DNA could not be extracted. Desperate to identify the body, a team of pathologists took a chance by analyzing the stomach contents of the maggots who were feasting on the corpse. Much to their surprise, they were able to extract the victim's DNA from the fly larvae — and successfully identify the body.
Analyzing the maggots who have conglomerated around a decaying corpse is nothing new. They're typically used to age crime scenes and determine if bodies have been moved around. However, a recent study suggested that it might be possible to extract DNA from the gastrointestinal tracts of fly larvae — but the approach was never attempted in an actual legal investigation.
Looking to change that, María de Lourdes Chávez-Briones, Marta Ortega-Martínez and their colleagues the Autonomous University of Nuevo León in San Nicolás, Mexico, decided to give it a shot.
Investigators had suspected that the badly burned body belonged to a woman who went missing 10 weeks prior to the discovery of the remains. So, the first analysis of the extracted DNA was to determine if the body was in fact that of a female's — and it was. For the subsequent test, the pathologists compared her maggot-extracted DNA with that of her father's (a standard paternity test called short tandem repeat (STR) typing). Their analysis revealed a 99.7% chance that the two were father and daughter, thus confirming the identification.
This is consequently the first reported case of taking human DNA from the gastrointestinal tract of maggots to identify a victim in a criminal case.
Details of their work can be found in the Journal of Forensic Sciences.
Other sources: New Scientist.
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