From Nature:
Does evolution have a soft spot for blondes? About 5–10% of people from Melanesia, a group of islands northeast of Australia, have naturally blonde hair — the highest prevalence outside Europe. Yet people from the region have the darkest skin pigmentation outside Africa.
Now, a study of people from the Solomon Islands in Melanesia shows that they evolved the striking blonde trait independently of people in Europe. This refutes the possibility that blonde hair was introduced by colonial Europeans, says Carlos Bustamante, a geneticist at Stanford University School of Medicine in Stanford, California, and a senior co-author on the study, which is published today in Science1. “Blonde hair has clearly evolved twice,” he says. To investigate the genetic basis underlying the trait, Bustamante and his colleagues compared the genomes of 43 blonde and 42 dark-haired Solomon Islanders, and revealed that the islanders' blonde hair was strongly associated with a single mutation in the TYRP1 gene. That gene encodes an enzyme that influences pigmentation in mice and humans. Several genes are known to contribute to blonde hair coloration in Europeans, but TYRP1 is not involved.
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