An American scientist has developed a technique that makes it possible to recover and sequence DNA from hair without the root, a development hailed as a “game changer” in criminal forensics, The New York Times reports. Several law enforcement agencies already have used the new method to extract genetic profiles from the hair of killers and victims in cold cases over the past 18 months.
Forensic scientists have long had to explain to juries why, contrary to what’s seen on TV, they can’t get sufficient DNA out of a hair unless it contains a root, which only a tiny percentage do. But Ed Green, a paleogeneticist at the University of California, Santa Cruz known in the scientific community for his work on the Neanderthal genome, created a series of technologies that enable extracting the needed genetic information from rootless hair, just as he has done with fossilized bones. Beyond one case in New Hampshire that authorities have said they cracked using Green’s technique, Green cannot share details of the investigations he’s involved in or with whom he is collaborating. He did say his point people are often Steve Kramer, a lawyer in the FBI’s Los Angeles office, and Barbara Rae-Venter, a genetic genealogist, the duo that solved the Golden State Killer case in 2018 by finding relatives of the suspect in a genealogy database, spawning a new approach to solving crimes. Suzanna Ryan and Green cautioned that the technique is unlikely to be used widely soon, as it is complicated and sequencing each hair costs several thousand dollars.