Move over fingerprints! A single strand of hair may soon be used to identify people, thanks to scientists who have found unique protein markers in the human hair - a finding that could be a game-changer for solving crimes.
DNA profiling is commonly used for identification in forensic science and archaeology because DNA is unique to each individual.
However, environmental and chemical processes can degrade DNA, limiting its usefulness over time.
In contrast, protein is more stable than DNA and can also have variations that may be unique to the individual.
Glendon Parker from the Lawrence Livermore National Laboratory (LLNL) in the US and colleagues studied whether the proteins found in human hair could offer another tool for identifying individuals in forensic or archaeology scenarios.
The researchers were able to examine bioarcheological hair samples from six individuals that were up to 250 years old, demonstrating the robustness of these proteins.
They analysed these samples along with hair samples from 76 living humans of European American and African descent.
They have found a total of 185 hair protein markers to date, which they estimate would be sufficient to provide a unique pattern for an individual that could distinguish that person among a population of one million.
The researchers hope to identify a core set of around a hundred protein markers that would be sufficient to distinguish an individual among the entire world's population using a single hair.
The new identification technique using proteins could offer another tool to law enforcement authorities for crime scene investigations and to archaeologists.
"We are in a very similar place with protein-based identification to where DNA profiling was during the early days of its development," said Brad Hart, director of the LLNL Forensic Science Centre.
"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," said Hart. The study was published in the journal PLOS One.