A gene that regulates melanin has a variant that is more common among Europeans and involved in early graying.
No matter who you are; for most of us gray hair is an inevitable part of getting older.
But what if you could switch off the gene that causes it?
For the first time, scientists have identified a gene called IRF4 as the culprit behind gray hair.
DNA samples from over 6,000 volunteers were collected in Latin America; chosen for the diverse ancestry of its inhabitants. And it turns out if you have your roots in Europe, gray hair is much more likely.
DR KAUSTUBH ADHIKARI, UNIVERSITY COLLEGE LONDON, CELL & DEVELOPMENTAL BIOLOGY:
"This genetic variant of IRF4 has two forms; one form is present world-wide and the other form is present only in Europeans. And we saw that this particular European specific form gives you almost double the chance of hair graying."
The gene IRF4 helps regulate melanin in the body, which determines - among other things - hair color. Age and environmental factors will, of course, influence how quickly IRF4 triggers hair graying. But the researchers say their discovery could lead to a treatment that could stop it in its tracks.
PROFESSOR ANDRÉS RUIZ-LINARES, UNIVERSITY COLLEGE LONDON BIOSCIENCES:
"Switching off a gene is of course feasible, the issue is whether it will have the desired effect and whether it's the right thing to do... But in terms of trying to develop a therapy to delay or prevent hair graying, that is something that is potentially feasible; yes."
That could be music to the ears for many, though in this market in London the mood was decidedly pro-gray.
UNIDENTIFIED MALE SHOPPER: "I don't mind going gray, I don't mind not going gray - I really couldn't care less."
UNIDENTIFIED FEMALE SHOPPER: "Go gray. Definitely go gray, go natural."
TWO MARKET STALL OWNERS:
ONE: "I think it's trendy, people like it"
TWO: "It shows my wisdom"
ONE: "Yeah absolutely, my father has got it right here"
TWO: "Father! What are you talking about."
(c) Thomson Reuters 2016