Scientists identify genes associated with grey hair, unibrows and balding

Scientists have found a whole host of genes associated with human hair growth - including, for the very first time, a gene they believe contributes to hair going grey.

The study, published Tuesday in Nature Communications, also plucks out genes associated with monobrows, eyebrow and beard bushiness, hair colour and shape, and balding.

“It was only possible because we analysed a diverse melting pot of people, which hasn’t been done before on this scale,” study author Kaustubh Adhikari of University College London said in a statement. Adhikari and his colleagues sifted through the genetic data of over 6,300 men and women from across Latin America, covering a wide range of ethnic backgrounds. By taking note of their intrinsic hair traits and comparing them to their genomes, they were able to weed out which genes were often correlated to the same traits.

The gene IRF4, which was already known to influence hair color by helping to make and store melanin - the substance that gives our eyes, skin, and hair their distinct shades - is now pinned to greying hair, too. Hair goes grey with age when pigment cells stop producing melanin. IRF4 doesn’t cause grey hair, but its presence seems correlated with an earlier loss of hair colour. That makes a lot of sense, since it was already associated with pale hair shades.

Many genes have already been identified as being associated with different hair colorus, shapes, and thickness - after all, it’s not as if one gene can produce red or blonde hair on its own without fail. In the same way, future researchers will certainly find other genes that contribute to a tendency for grey hairs. But the new study has at least found one culprit for researchers to focus on, as well as painting a more complete picture of the genetic profiles behind other hair types.

Bushy eyebrows were associated with a gene called FOXL2, and a gene called EDAR - often associated with East Asian hair types - seemed to help hair on top of the head grow straight while keeping facial hair sparse. A gene known as PRSS53 is now one of several linked to curly hair.