University College London study names IRF4 as the gene that causes hair to turn grey

For the first time, scientists explain why human hair turns grey. The identification of a specific gene as the cause of the change in colour of hair confirms it is something passed down the generations.

A study, published in Nature Communications and made by University College London (UCL) researchers, which analysed the genomes of over 6,000 people from different races across Latin America, identified 18 genes that apparently influence hair traits. The traits covered hair shape, colour, balding pattern, beard, eyebrow, mono-brow and baldness.

For greying hair, the study points to the gene IRF4, reports Gizmodo. The gene is involved in regulating the production and storage of melanin, the pigment that decides eye, skin and hair colour. When the hair becomes grey, it means melanin in absent in the hair.

But the scientists say that over the years, more discoveries about genes that contribute to the greying of hair – considered both a sign of wisdom and advancing age – would take place. They add that understanding how IRF4 influences hair colour could help in the development of hair products that changes the hair’s appearance when it grows in the follicle by slowing or stopping the greying process.

Dr Kaustubh Adhikari, lead author of the study and from UCL’s beaCell & Development Biology department, explains identifying the specific gene became possible because of the team’s analysis of a “diverse melting pot of people” done for the first time on that scale. He says the discovery, more than just serve as a guide for beauticians, have potentials for forensic and cosmetic applications as science acquires more knowledge on genetic influence on people’s appearance.

He specifically says the discovery could help forensic DNA technologists build visual profiles based on a person’s genetic makeup. There had been previous studies on people of European descent. Adhikari says that the new results could assist in forensic reconstructions for people of Latin American and East Asian lineages.

Part of the study, made by researchers at the Centre for Skin Sciences of the University of Bradford, is identifying also the gene that influences hair curliness, which is Protease Serin S1 family member 53 (PRSS53). Finding the new variation in PRSS53 “provides an important insight into the genetic controls underpinning scalp hair shape and texture,” explains University of Bradford Professor Desmond Tobin.