A blond boy from the island of Vanatu
In many places, blond hair usually goes with white skin and European ancestry. But in the islands of Melanesia
and among the Aborigines of Australia, blond hair crops up on dark-skinned people with no known European heritage. Scientists have long wondered, is it because they have some (very, very) long-lost European ancestors? Or did blond hair arise from a genetic mutation in the population there? A paper
published in Science this week lays that question to rest. The researchers found that blond Solomon Islanders in Melanesia have a single amino acid difference in the tyrosinase-related protein 1
(TYRP1) gene, which codes for an enzyme involved in the production of the pigment melanin. Other mutations in TYRP1 can give people albinism
; this one gives them light-colored hair. The mutation is recessive, so only people who have two mutant copies of the TYRP1 gene are blond. This mutation is not responsible for European blondness, which hammers home the fact that pale hair didn't arrive on a boat with early European explorers---it's definitely native to the islands. For the full story and lots of tasty genetics, head over to Discover's Gene Expression blog, where Razib Khan dissects the paper
.
Image courtesy of Muntuwandi / Wikimedia Commons
