Grey hair could be banished forever after scientists found the gene responsible, which they believe can be turned off.
Spotting the first grey hair is a disheartening rite of passage for most people.
But a major breakthrough by British scientists could mean that future generations will no longer suffer the inevitable indignity of the ageing process.
Grey hair is caused by the depletion of melanin, which is responsible for the pigment in hair, skin and eyes, making blondes lighter and brunettes darker.
Although fashion’s vanguard have popularised the shade in recent years, going grey is still viewed as an alarming sign of ageing, and Britons spend £3 million a year on over-the-counter hair dyes.
Scientists had known that a gene called IRF4 played a crucial role in hair colour, but for the first time they were also able to link it to going grey.
“We already know several genes involved in balding and hair colour but this is the first time a gene for greying has been identified in humans, as well as other genes influencing hair shape and density,” said lead author, Dr Kaustubh Adhikari, UCL Cell & Developmental Biology.
“It was only possible because we analysed a diverse melting pot of people, which hasn’t been done before on this scale. These findings have potential forensic and cosmetic applications as we increase our knowledge on how genes influence the way we look.
“Preventing grey hair is a possibility and even reversing grey hair might not be impossible. Once we know more about the pigmentation process, and all the genes involved it should be easy to find a protein or enzyme to up-regulate or down-regulate the activity.”
To find out what was causing greying hair, the team analysed DNA samples of more than 6,600 volunteers recruited in Brazil, Colombia, Chile, Mexico and Peru. The group included individuals of mixed European (48 per cent), Native American (46 per cent) and African (6 per cent) ancestry, giving a large variation in head hair appearance.
Visual traits for each individual were compared to whole genome analysis results to identify the genes driving differences in appearance.
The gene identified for grey hair – IRF4 – is known to play a role in hair colour but this is the first time it was also seen to be responsible for the greying of hair.
The finding could mean that changing hair or eye colour could be possible without using dyes. It would simply be a matter of taking a drug which changed the expression of certain genes to alter appearance, turning blondes into brunettes or preventing grey hair.
Professor Andres Ruiz-Linares, UCL Biosciences, who led the study, said: “We have found the first genetic association to hair greying, which could provide a good model to understand aspects of the biology of human aging.
“Understanding the mechanism of the IRF4 greying association could also be relevant for developing ways to delay hair greying.”
The team have also discovered several other genes which play crucial role in physical appearance. EDAR was found to be linked to the ability to grow a full, bushy beard while eyebrow thickness was found to be determined by FOXL2. Likewise a variant of PAX3 made a monobrow likely, while PRSS53, which was found to influence hair curliness.
“An enduring fascination of human evolution has been our peculiarly luxuriant scalp hair, and finding a new variation in the PRSS53 gene provides an important insight into the genetic controls underpinning scalp hair shape and texture,” explained Professor Desmond Tobin, University of Bradford who investigated PRSS53 at the Centre for Skin Sciences as part of the study.
“The PRSS53 enzyme functions in the part of the hair follicle that shapes the growing hair fibre, and this new genetic variation, associated with straight hair in East Asians and Native Americans, supports the view that hair shape is a recent selection in the human family.”
The findings could also help develop forensic DNA technologies that build visual profiles based on an individual’s genetic makeup. For example it would be clear that a suspect had curly hair, had grey hair, or had blue eyes simply by looking at their genetic make-up.