Beautiful.
Black People with Naturally Blonde Hair
By Tracey Wallace of NaturallyCurly.com
Hair is simply amazing. The human body and the mechanisms by which it adapts to its environment are mind boggling, and our hair color, texture, porosity and everything else plays a massive part in how well we succeed in a particular environment (or at least it did before we started living in these air conditioned covered boxes).
We all love and nourish our hair, but it’s so easy to forget just how magical these dead cells growing from out of our scalp really are.
Enter the Melanesians, a native group of people living on the Soloman Islands northeast of Australia famous for their beautiful dark skin and naturally blonde hair. Yep, that’s right. They don’t sport weaves, wigs, extensions, permanent dye, temporary dye, some weird henna reaction, or whatever else anyone uses to get the blonde look that’s so typical of the caucasian persuasion. Ten percent of these islanders actually come by it naturally.
The odd combination has got scientists wondering about how such a color combo develops over time. According to the Global Financial Newswires, many scientists have long thought that their blonde hair was a result of a diet high in fish, perhaps bleaching by the sun and salt water, or a reminder of the island’s historic relations with people of European descent.
In fact, the blonde Melanesians have blonde that is unique solely to them. According to the study in which scientists compared 43 blonde hair islanders to 42 dark hair islanders, blonde Melanesians have a variant of a native gene called TYRP1 that plays an important role in the melanin biosynthetic pathway. This variant is completely separate from what causes blonde hair in Europeans, and doesn’t even exist in the European genetic set.
What’s truly beautiful in this fascinating discovery, as so perfectly stated by the study author Sean Myles, a geneticist at Nova Scotia Agricultural College, is that “it’s a great example of convergent evolution, where the same outcome is brought about by completely different means.”
And that makes hair of all textures, types and colors absolutely unique and absolutely beautiful.
Blond Hair of Melanesians Evolved Differently Than Those of Europeans
May 7, 2012
A new study of the people from the Solomon Islands in Melanesia, a group of islands northeast of Australia, has shown that blond hair evolved differently, genetically speaking, than in Europeans. About 5-10% of the people in Melanesia have naturally blond hair, which is the highest prevalence outside of Europe.
This refutes the hypothesis that blond hair was introduced by colonial Europeans. Carlos Bustamante, a geneticist at Stanford University School of Medicine, in California, and his team published their findings in the journal Science.
Bustamante and his colleagues compared the genomes of 43 blond and 42 dark-haired Solomon Islanders. This revealed that the blond hair was strongly associated with a single mutation in the TYRP1 gene, which encodes an enzyme that influences pigmentation in mice and humans. In Europeans, several genes are known to contribute to blond hair, but TYRP1 isn’t involved.
They compared DNA between more than 900 Solomon Islanders and 900 other people from 52 populations around the world to find that the TYRP1 mutation is probably unique to the Oceanic region that includes Melanesia. About one-quarter Solomon Islanders carry the recessive gene, so two copies are needed to have blond hair.
However, not all occurrences of blond hair are the result of this particular mutation, but researchers have predicted that it accounts for about 30% of cases. Another 16% are attributed to age and gender (young children and women are more likely to have blond hair), while the rest is attributed to sun exposure and other undiscovered genes. It’s unusual that one specific mutation accounts for such a large proportion of an observable trait in a population.
Bustamante thinks that this mutation might have arisen between 5,000 and 30,000 years ago, but hasn’t been able to explain why it has reached such a high frequency in the Solomon Islands.
[via Nature]
Genetics of blond hair in Solomon Islanders
- 05 May 2012 11:27:18 GMT
The evolution of blondes has been disputed for centuries. No, not in the pub. The European style blond(e) found from Lebanon to Scandinavia and, of course in Australia and North America, now has competition. For years, jokes about sailors misleadingly explained Solomon Islanders blond locks.
Now this intriguing solution has appeared from a pretty old and worn problem. About 46% of all Solomon Islanders are blond, despite there being no explanation whatsoever for their hair colour in an equatorial archipelago, far to the north-east of Australia and east of PNG.
Sean Myles and his colleagues at Bristol, Max Planck Institute and UC San Francisco investigated the Melanesians on the Solomon Islands, publishing their research in the journal of Science. Initially sampling the saliva and hair of 1209 islanders, they were able to pinpoint a single gene type of inheritance immediately. Looking more closely at the genomes of 85 people confirmed that the blonds had a different version (allele) of the TYRP1 locus from the dark-haired individuals.
Situated east of Papua New Guinea and north of Vanuatu, The Solomons are almost central to the Melanesians colonisations - Oceania image via Shutterstock
TYRP1 is well known to create albinism in humans and lightness of colour in mice, dogs and horses. In fact we believe that blonde mice do actually have more fun. This system does not create the blond(e) pigmentation with which we are all familiar. The Melanesian brand of blond has arisen separately, indicating that such isolated communities could have many more (if less obvious) genes that could benefit us.
Medical research could be happily overtaken by currently unknown "resistances" or "immunities". Even some of the most despairing medical problems could be alleviated if we find more genomic variation. The authors point out that it is folly to know the ancestry of western people form genomics while the basic constitution of minor human groups needs to be known for their sakes and ours!
Enjoy your genetically modified tea and peruse a TV screen full of modified brunettes. while considering how often blondes might have been evolved. Maybe some prehistoric lady found it hard to find a gentleman with her early blondness convergence. This guy certainly seems to enjoy the Solomon Islands - but of course, the Solomons' gene is much more common there than blondness in any European country.
Read more at http://www.earthtimes.org/health/solomon-islands-blonds/1967/#Ba6Z4rKJ47IhUEdv.99
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