Police could soon identify criminals with just a strand of hair

Julie Russell/LLNL

It is a known fact that when a human being breathes its last, it continues to leave a mark for millennia to come. Both the criminal investigators and archaeologists regularly rely on DNA for human identification. But environmental conditions like heat and light can severely deteriorate the evidence, thus proving DNA identification ineffective.

This is where researchers from Lawrence Livermore National Laboratory step in with their newly discovered method of identifying humans based on hair protein markers. These markers are much more resilient than DNA (with traces of protein found in human hair more than 250 years old) and are unique in terms of marker count and patterns to every single person. Once the method is fully optimized, the scientists believe they could distinguish an individual among the world’s population using a single strand of hair.

“We are in a very similar place with protein-based identification to where DNA profiling was during the early days of its development. This method will be a game-changer for forensics, and while we’ve made a lot of progress toward proving it, there are steps to go before this new technique will be able to reach its full potential.” says LLNL chemist Brad Hart, the director of the Lab’s Forensic Science Center and co-author of a paper detailing the work.

It doesn’t mean that DNA profiling will be left out in the cold. This method still requires some major refinement before it could be widely used as an alternative in crime labs. As it stands now, the current technique is already able to identify one person out of a million and the whole process requires roughly 2,5 days to complete. But once the researchers improve the process, it could revolutionize how criminal forensic investigations are conducted in the future.

According to a study, the researchers examined male and female hair samples for 66 European-Americans, five African Americans, five Kenyans and six skeletal remains from the 1750s and 1850s, finding a total of 185 protein markers so far. Each person’s number of hair protein markers, combined with their pattern of protein markers, is unique.

The authors believe that the number of individual protein markers that can be used to differentiate people could go as high as 1,000. Furthermore, they seek to establish a set of 90-100 protein markers that would be sufficient to distinguish an individual among the world’s population using a single hair.

Beyond the obvious use in crime investigation, it could easily be used to confirm one’s lineage through remains dating back multiple generations. While it won’t kiss DNA analysis goodbye overnight, it is still deemed an important breakthrough for the forensic science.

Michal Madaras

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