Some Europeans have enhancers that make them blond. In this case, the enhancer isn’t a hair dye, but a genetic variation that controls pigment production in hair follicles, David Kingsley, an evolutionary geneticist at Stanford University and colleagues report June 1 in Nature Genetics.
Previous studies had indicated that a genetic variant known as a single nucleotide polymorphism, or SNP, is associated with blond hair in Europeans. Why the variant affects hair color wasn’t clear because it is not part of a gene. Now Kingsley’s team provides evidence that the blond-inducing variant lies within a piece of DNA known as an enhancer. Enhancers are stretches of DNA typically located far from genes that nevertheless help control gene activity.
Read the full, original story: How a genetic quirk makes hair naturally blond