Going gray may seem like an inevitable fact of getting older, but a hair gene might help scientists determine who is more likely to lose their color.
The new study linked gene IRF4 to a loss of pigment that results in gray hair. Though the gene has previously been linked to hair color, this is the first time it's been associated with the graying of hair.
"We already know several genes involved in balding and hair color, but this is the first time a gene for graying has been identified in humans, as well as other genes influencing hair shape and density," lead study author Dr. Kaustubh Adhikari, of the UCL Research Department of Cell and Developmental Biology, said. "It was only possible because we analyzed 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."
Researchers examined DNA samples from more than 6,000 volunteers recruited in Brazil, Colombia, Chile, Mexico and Peru. The study sample included a mixed group of individuals that were 48 percent European, 46 percent Native American and 6 percent African, representing many different hair types.
During the study, researchers also assessed if any of the participants were balding or going gray and the general color and shape of hair in both men and women. Beard, eyebrow thickness and monobrow were also measured, but only in male participants.
Findings showed additional genes linked to hair, including EDAR for both beard thickness and hair shape. The gene FOXL2 was also discovered, which was linked to eyebrow thickness and PAX3 for monobrow prevalence. Lastly, researchers found gene PRSS53, which influences the curliness of hair.
The study authors said they are hopeful the findings could help in developing new forensic DNA technologies for one day building visual profiles in Latin America and East Asia.
"It has long been speculated that hair features could have been influenced by some form of selection, such as natural or sexual selection, and we found statistical evidence in the genome supporting that view," Adhikari said. "The genes we have identified are unlikely to work in isolation to cause graying or straight hair, or thick eyebrows, but have a role to play along with many other factors yet to be identified."
The study was published today in the journal Nature Communications.
