Solomon Islands 'blond' gene is found: study

Dark-skinned, blond-haired indigenous people on the Solomon Islands have a gene that is unique to the South Pacific nation and was not picked up from interbreeding with Europeans, scientists said Thursday.

Outsiders have long presumed the unusually fair-haired Melanesians were a result of long-ago liaisons with European traders, while locals often attributed their golden locks to a diet rich in fish or the constant exposure to the Sun.

But the reason why some five to 10 percent of the islanders are blond comes down to simple genetics -- a gene called TYRP1 that natives of the possess but Europeans do not, said the study in the US journal Science.

"So the human characteristic of blond hair arose independently in equatorial Oceania. That's quite unexpected and fascinating," said lead author Eimear Kenny, a postdoctoral scholar at Stanford University in California.

Researchers gained the trust of a local chief and collected data from 1,000 people, including hair and assessments, blood pressure, height and weight and saliva samples for DNA.

The lab analysis on samples from 43 blond and 42 dark-haired natives began in September 2010 and "within a week we had our initial result," said Kenny.

"It was such a striking signal pointing to a single gene -- a result you could hang your hat on. That rarely happens in science."

The idea to study the genetics of the population came from co-author Sean Myles, a former Stanford postdoctoral scholar who is now an assistant professor at the Nova Scotia Agricultural College, after a trip there in 2004.

"They have this very dark skin and bright blond hair. It was mind-blowing," said Myles.

"As a geneticist on the beach watching the kids playing, you count up the frequency of kids with blond hair, and say, 'Wow, it's five to 10 percent.'"

Co-author Carlos Bustamante, professor of genetics at Stanford, said the study gives good cause for more research on the genomes of rarely studied populations.

"Since most studies in human genetics only include participants of European descent, we may be getting a very biased view of which genes and mutations influence the traits we investigate," Bustamante said.

Nic Timpson from the Medical Research Council Centre for Causal Analyses in Translational Epidemiology at the University of Bristol was a co-author on the report.


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May 03, 2012
Clearly its a result of contact with Europeans

May 03, 2012
@ T j McBearsNYC
A binary denial of the assertion in the opening paragraph contributes nothing here, besides demonstrating a want of critical thinking. This is a science forum. What evidence do you present to argue against the findings reported above please??

New Zealand Maori also have a blonde hair expression, evident prior to colonial contact with whites; it would be interesting to see if this too is TYPR1.

May 03, 2012
This is a form of albinism. "Mutations in the mouse Tyrp1 gene are associated with brown pelage, and in the human TYRP1 gene with oculocutaneous albinism type 3 (OCA3)."

May 05, 2012
It is strange that a blond gene would be common in an equatorial population. In Northern Europe blond hair is a valuable adaption which saves the body from wasting resources on unnecessary melanin production, and probably also allows more sunlight to strike the skin and produce vitamin D. But in Melanesia there is too much intense sun, and blonds would seem to be at a disadvantage. I suspect that this mutation has an additional effect besides causing blond hair, and this other effect has benefits which cause the mutation to be a successful adaptation.

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