Gene for greying hair identified

They may not have settledthe enduring debate over whether grey hair makes a person lookdistinguished or just plain old, but scientists have identifiedfor the first time a gene behind greying hair.

Researchers said on Tuesday an analysis of DNA from morethan 6,300 people from five Latin American countries enabledthem to pinpoint a gene that affects a person's likelihood ofgetting grey hair.

The gene, called IRF4, is involved in regulating melanin,the pigment responsible for hair colour as well as the colour ofthe skin and eyes.

People with a certain version of the gene are predisposed tohair greying, according to University College London humangeneticist Andres Ruiz-Linares, one of the researchers in thestudy published in the journal Nature Communications.

The researchers said hair greying is not driven exclusivelyby genetics, with other factors in the mix such as stress orexperiencing a traumatic event.

"This is really the first study on the genetics of hairgreying in humans," University College London statisticalgeneticist Kaustubh Adhikari said.

Prevention, reversal may be possible

People spend a lot of time and money dyeing grey hair backto their natural hair colour. The researchers said identifyingthis gene could offer a path forward for developing a treatmentthat could prevent or reverse greying.

"A drug that has effects on the melanin-production pathwayin hair follicles as the follicles develop internally mightreduce the need to apply external hair dyes on the scalp hairafter it comes out. This is certainly a research avenue worthpursuing," Kaustubh said.

The researchers combed through genetic information from menand women in Brazil, Colombia, Chile, Mexico and Peru, with acombination of European, Native American and African ancestry.

European ancestry

The gene variant predisposing people to early hair greyingwas essentially only seen in those of European ancestry.

"Thismight, to some extent, explain why hair graying is more commonin Europeans than in other populations," Ruiz-Linares said.

One of the researchers brushed aside the issue of whether ornot grey hair is attractive.

"Personally I don't have much of a view regarding the socialresponse to hair greying, but I find it an interesting model tostudy aging in general," said Desmond Tobin, a hair follicle andpigmentation biologist at Britain's University of Bradford.

The study also identified genes related to other hair traitsincluding curliness, beard thickness, eyebrow thickness and
predisposition for eyebrows that join together, known as unibrowor monobrow.