Chileans pioneer new technique to extract DNA from teeth

Breakthrough will help experts identify long-deceased bodies, estimate time of death and even ascertain cause.

The relatively new field of forensics has already revolutionised the way police can solve crimes or ascertain circumstances of fatal accidents. Now, thanks to a breakthrough by Chilean scientists, further progress has been made in this cutting edge field.

By extracting DNA information from human tissue, experts can create genetic profiles of the deceased, therefore providing a key tool in the quest to identify remains many years later. This technique is also useful in cases where the circumstances of the person’s death, in a natural disaster or a plane crash for example, rules out traditional methods of forensic identification.

A problem, however, arises when even soft tissue is not available. In these cases, dental samples become key to identifying victims. Traditionally, the process of extracting DNA from teeth has been fraught with problems as the dental sample itself is often destroyed in the process and the DNA lost as a result.

Chilean scientists Patricio Carrasco and Carolina Inostroza both based in Santiago’s Universidad de Los Andes Odontology Department have found a way to overcome this obstacle. The new technique they pioneered uses cutting-edge technology to allow both more accurate and complete DNA information to be extracted from dental samples while also ensuring the tooth fragment is not destroyed in the process.

The pioneering new process re-hydrates the dental sample by exposing it to body temperature (37°) creating the ideal conditions for collecting DNA samples. Something never achieved by previous techniques according to Carrasco in an interview with La Tercera.

Currently, bone samples often provide DNA that is either insufficient in quality, quantity or both.

“This primarily occurs in cases where the victim has been dead for several years or when remains have been damaged or contaminated,” explains Carrasco. “Our methodology provides good quality DNA and in sufficient quantity even in cases where samples are 20 years old.”

The upshot of this scientific wizardry is that experts will not only be able to identify the identity of remains but also estimate further information about the circumstances of the death and even investigate the presence of drugs, poison or heavy metals in samples. Thanks to this discovery, experts and authorities may be able to shed new light on long unsolved crimes or mysterious deaths.

This discovery by the Universidad de Los Andes staff comes soon after news of Chilean universities being recognised internationally for the high quality research taking place within several prestigious institutions.

By Sam Edwards