Monday, October 1, 2007

Red Spotlight: #12

The Sunday Times
January 07, 2007

Flaming Heck, First Brits Were Redheads

A genetic study has revealed a surprise about our ancestors, says Robin McKie

There is a small, windowless room on the ground floor of Oxford’s Radcliffe Infirmary that can be reached only by walking through a maze of narrow passageways. The hospital, built in the late 18th century, is old even by the normal standards of ageing National Health Service buildings. Nevertheless, it is in these antiquated surroundings that scientists have set up one of the most ambitious biological programmes attempted in Britain.
This is the base of the People of the British Isles project, which is using the power of modern genetics to show how people in different regions interacted over the past few thousand years, how they subjugated one another and how they passed on ideas, inventions and art.
In that little cubbyhole on the ground floor there is a bench fitted with high-technology gear used to isolate and copy DNA, a couple of tables with personal computers and several tall fridges. Inside these are rows of vials that hold the bloodline of the British people. Each vial contains DNA from a person who has taken part in the project and each sample has its own special story to tell.
Blood was collected from 11 sites for the project’s pilot study: Orkney, northeast England, Cumbria, Lincolnshire, Norfolk, Suffolk, Oxfordshire, Pembrokeshire, Kent/Sussex, Devon and Cornwall. The researchers then used centrifuges to isolate the white cells, which are stuffed with DNA. Using the DNA — and thanks to advances in molecular biology — the team has begun to build up a pattern of different genetic variants for different parts of the British Isles.
From the moment they started to pull data from their machines, their findings produced fascinating information about one of the most conspicuous aspects of the British and Irish population: our redheads. Whether they are called carrot-tops, ginger-heads or “Titian blondes”, these people are blessed — or cursed, according to some of them — with flaming locks that have been a feature of people for millenniums, from Boudicca to Prince Harry.
The underlying causes of the condition were recently disentangled by a team led by Professor Jonathan Rees, a dermatologist based at Edinburgh University. It was discovered that hair colour is controlled by a gene called the melanocortin 1 receptor, or MC1R. Genes come in different variants and there are about 70 different versions of MC1R. Rees discovered that a subgroup of about half a dozen is closely involved in determining if a person will be red-haired or not.
“If you have one of these variants, your chances of having red hair are increased four or five times above the average,” said Rees. “However, if you have two of these variants — one inherited from your mother and one inherited from your father — your chances of being red-haired increase to 30 to 40 times the average.”
(This is exploited by forensic scientists when testing blood left behind at crime scenes. If they find two MC1R variants, police know there is a strong chance the culprit will be a redhead.)
Red hair today is generally associated with the Scots and Irish, but there have been no consistent efforts to establish the prevalence of the condition.
“It has actually become harder to find the prevalence of red hair today,” said Rees. “More and more women — and some men — now dye their hair and we simply have no idea if a redhead is a real one or if a blonde is a redhead under the dye. As a result the incidence of red hair in Britain is still a bit of a mystery.”
Enter the scientists of the People of the British Isles project: thanks to their efforts, this most distinctive characteristic is now opening up its mysteries for the first time. Testing their white cell samples for two of the half-dozen red-hair versions of the MC1R gene, they were able to show their frequency in each area of the British Isles. The results were intriguing.
Where one is the maximum value, they got figures of 0.16 and 0.23 for the frequencies of red-hair genes in Cornwall and Devon. The frequency in Oxfordshire was 0.07; in Sussex and Kent 0.13; in northeast England 0.11; in Lincolnshire 0.07; and in Cumbria nil. In Wales the figure was 0.21, and in Orkney a high 0.26. But the highest was in Ireland. Using data from other research studies, the team got a figure for Ireland of 0.31, confirmation of the stereotypical image of the red-haired Irishman.
The results are remarkable, as Sir Walter Bodmer, the Oxford geneticist leading the project, acknowledges: “I was amazed at them. I didn’t expect to see something like this.”
The research gives us, for the first time, an insight into the startling numbers of native people who have been described as having red hair in ancient times.
Famous British redheads include Queen Boudicca, who rebelled against the Romans and sacked London in AD60. She was described by Dio Cassius, the Greek historian, as being “tall and terrifying . . . a great mass of red hair fell over her shoulders”.
Over the centuries there have been many other famous red-haired Britons, including Elizabeth I, Oliver Cromwell, Nell Gwyn and Winston Churchill.
Nevertheless, today red locks are mainly associated with only certain areas, with Scotland being the principal focus in mainland Britain. Prominent Scots “ginger-heids” include Gordon Strachan, manager of Celtic, and Charles Kennedy, former leader of the Liberal Democrats.
But why do we have such numbers in these parts of the British Isles today and not others? The answer, says Bodmer, is that red-hair genes were common among the first Britons and that populations in the archipelago’s fringes still carry their bloodline.
“Genes for red hair first appeared in human beings about 40,000 to 50,000 years ago,” agrees Rees.
These genes were then carried into the islands by the original settlers, men and women who “would have been relatively tall, with little body fat, athletic, fair-skinned and who would have had red hair”, says David Miles, of English Heritage.
Redheads therefore represent the land’s most ancient lineages. So if you want an image of how those first people appeared, don’t think of a hairy savage with a mane of thick black hair. Contemplate instead a picture of a slim, ginger-haired individual: Prince Harry, perhaps, or the actress Nicole Kidman who has Scottish and Irish descent.
Why did those early Britons have so many redheads in their midst in the first place? Is there an evolutionary advantage to having red hair in this part of the world? According to Rees, the answer may be yes.
The MC1R variants that cause red hair also have an effect on the skin. As a result, redheads do not make enough of the dark pigment melanin to protect them against the sun’s powerful ultraviolet rays. Their skin rarely tans. It just burns or freckles.
In Africa, where modern humans first evolved 150,000 years ago, this would have been fatal. In northern Europe, however, melanin-free skin could have provided an advantage because we make vitamin D in our skin when sunlight shines on it.
Dark-skinned people were protected against the African sun, but their ability to make vitamin D would have been badly affected in relatively gloomy northern Europe. This could have caused rickets, resulting in weak bones and curved legs — bad news for a hunter-gatherer. Rickets is particularly damaging for women, as it increases pelvic deformations, raising the risk of death in childbirth. So, the theory goes, we evolved white, melanin-free skin that has no dark pigment to block sunlight and cause rickets. Red hair was a side effect.
So there it is: being a redhead could mean you possess an evolutionary advantage over non-red-haired people. Or it could simply be a matter of luck. Those MC1R variants may have appeared by chance and survived in northern Europe where they caused no harm.
Scientists in the United States and Britain have uncovered another surprising aspect to having ginger locks. Researchers have found that red-headed women are better able to tolerate pain than anyone else, including red-headed males. This is due to a protein produced by MC1R that does one thing in the skin and hair and another in the female brain.
At the human genetics unit at the Western general hospital in Edinburgh, Professor Ian Jackson has launched a study of redheads in the hope of developing new painkillers in the wake of this discovery and has found that redheads are better able to tolerate intense heat.
As a result, he is preparing to test the hypothesis that redheads should be able to tolerate hot spicy foods better than other people. Thus our ancient, divergent origins seem to have equipped some Britons with the ability to deal with one of the most powerful challenges of modern life: the vindaloo.

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