Seven faces of Eve
01.09.2001 The man who narrowed our European ancestors to seven separate women talks to GILBERT WONG about mitochondrial DNA and the emotion of origin.
Ursula, Xenia, Helena, Velda, Tara, Katrine and Jasmine. If you or your kin can say you came from Europe then these are the names of your clan mothers.
These are the prolific women, the maternal archetypes, or earth mothers who gave birth to those who would become today's 650 million modern Europeans.
The claim that every individual European can claim a direct line of descent to at least one of these seven women who lived between 45,000 and 20,000 years ago is fantastic and logical.
Logical because if we pause to think, any genealogical tree will narrow down to one founder. Fantastic because science lets us see back through millennia in prehistory to these women and say that each of their descendants in modern Europe carries a little piece of biological material that has endured for up to 45,000 years. These women were lost to time but no longer.
The man making the claim is Bryan Sykes, professor of human genetics at Oxford University. His book The Seven Daughters of Eve, outlining his theory, is a rollicking read of scientific inquiry, adventure and adversity. From his home Sykes, 53 and feisty, hardly sounds like an Oxford don.
"Bollocks," he responds to a question during our interview.
Sykes can be controversial. His fondness for bold statements and the commercialisation of gene technology has started scientific stoushes which he seems to be winning. The very act of naming these clan mothers could be called an act of gall by some scientists.
Sykes disagrees: "What I wanted to do was bring them to life as individuals."
Sykes' field is the study of the genetics of human populations. But whereas traditionally, whole populations were compared with others to determine how humans came to people the world, Sykes has firmly turned the focus to the individual.
"There was no consideration of individuals, everything was done on the basis of groups. So everyone was given average characteristics," he says. "There's no better way to bring people to life than to give them names. Of course, we don't know their names.
"But there is not any disagreement that they existed. On the question of whether I should have given them names, I would say there has been a resounding silence of mild disapproval."
Sykes gives a metaphorical shrug of his shoulders.
"I do feel that professional academics do tend to want to keep things to themselves. Giving them names brought it to people's attention and that's good. Why should
academics have a monopoly on this history of the world?"
Sykes' work springs directly from New Zealand-born scientist Allan Wilson who had an illustrious career at Stanford University in California. Recipient of a MacArthur "genius" grant, Wilson, who died in 1991, was a controversial figure because he first suggested that a certain type of DNA called mitochondrial DNA or mDNA could be used to explore human origins. Mitochondrial DNA sits in the periphery of all human cells. Sperm cells jettison mDNA once they've fertilised an egg. So mDNA is only passed down the maternal line. What Wilson realised is that when mDNA is replicated in a son or daughter it remains a carbon copy of the mother's mDNA. Natural mutation is the only reason for the structure of mDNA to change.
Wilson created a molecular genetic "clock", its chiming based on the rate of natural mutation. Using his "clock" Wilson transformed the study of human origins with his theory of the African Eve. Some 150,000 years ago, argued Wilson, there was a woman who lived on the savanna of Africa who was the maternal ancestor of all of the six billion people now alive.
Sykes has refined the molecular clock by locating a "control region" within mDNA which allowed his team to categorise genetic clusters and estimate change over shorter periods of time.
Through a mixture of persistence and argument Sykes was given permission to take dentine from a tooth in the fossil jaw of Cheddar Man, an early European who lived some 10,000 years ago. After amplifying the sample, Sykes compared it to samples from modern Europeans. It was identical. Theories about our origins would never be the same again. Irrefutably, Sykes can say that race does not exist as a concept. We are all mongrels, he says and have been so for at least the past 10,000 years.
In Britain his research has been misused by the British National Party to support its platform that Britons have always been white. Raise the subject of its misuse and Sykes responds with a hearty "What a load of bollocks."
There is no biological justification for ethnicity, he says. "Even the idea of a population as an integral biological breeding group has been shown to be completely wrong. People have just done what they always do, they move, perhaps for a better life, they intermarry."
Serendipity could be his middle name. Rather than view history or even prehistory as determined by mass movements, Sykes believes that individuals and luck make history. In his book he recounts that if not for a moped accident which left him stuck in Rarotonga, he would not have begun his earlier work that helped to solve the origin of the Maori.
Work he began in Rarotonga eventually provided evidence of the path the Polynesians sailed to colonise the Pacific in a grand sweep of epic ocean voyages that had their origins somewhere in Indonesia, possibly the Moluccas, out to the Pacific, to Hawaii in the north, to Easter Island (Rapanui) in the east and New Zealand in the south.
The DNA evidence Sykes produced refutes the ideas put forward by Thor Heyerdahl of Kon-Tiki fame that the Polynesians came from South America and matches archeological evidence in pottery and Maori oral tradition exactly.
His point about the nonsense of race is made by a side discovery that up to 30 per cent of present-day Pacific Islanders share European DNA, a legacy of whalers, seafarers and missionaries who began to arrive in numbers only 200 years ago.
There are more New Zealand links to Sykes' work. He's an Oxford College friend of former National cabinet minister Simon Upton whom Sykes visited on his trek to gather Maori DNA in late 1990. At the time he bought a Jaguar in Blenheim and freighted it back to England.
Dunedin is also home to the woman who has become his nemesis, biochemist Erika Hagelberg of the University of Otago. Sykes' work stands or falls on the view that mDNA is perfectly replicated from generation to generation.
Research by Hagelberg on the island of Nguna in Vanuatu indicated that mDNA was not a "pure" copy. Hagelberg published research on mDNA that pointed to it being "recombinant" or mixed. If she was right then the edifice upon which Sykes had built his reputation on would crumble.
Hagelberg worked in Sykes' laboratory in the 1980s but left under a cloud which neither will expand upon in public.
Sykes: "It was a blow. Loads of people who didn't think much of mDNA seized upon it. Erika Hagelberg is not a classical geneticist, but nonetheless she did publish a paper that said she had evidence of recombination in mDNA.
"Only by chance I found that I had samples from the very same island and I couldn't see anything at all. I knew almost at once that there was something wrong. I did get in touch with her. Scientific etiquette should mean that if you have a serious doubt then you would be supplied with material so it could be retested, that's the whole basis of science. It was difficult to get samples from Erika. Ultimately, 18 months after I raised the matter, she retracted the paper."
And why did she retract? Sykes: "Because of the pressure. The reputation of mDNA was spiralling downwards. She did find that she had made an error.That only takes a week to check, not 18 months, and I make it plain that I disapproved of that episode."
This week Hagelberg was on a research trip to a remote part of Vanuatu and could only be contacted by e-mail. Her response: "My general comment is that Sykes overstates his case."
And certainly research published since Sykes' book was published points to a far less pat and satisfying conclusion. Instead of 95 per cent of modern Europeans carrying DNA that can be traced back to seven archetypal mothers, it says that only 76 per cent of Europeans can trace their origins to 11 such women.
Sykes agrees that his Seven Daughters theory may not be the last word on the matter.
"It really depends on what you call a clan and that depends on where you draw the boundaries. It's like looking at an oak and seeing large branches coming off and if you look at it, is this a big branch coming off or is it one or two?
"This is a field that isn't 100 years old. Things will change, there are plenty of places in Europe that we've never been to. There could be a clan there."
Another source of controversy is Sykes' privatisation of genetic technology.
His company Oxford Ancestors offers mDNA tests at a price to a public hungry to trace their prehistoric origins. The company processes 100 requests a day from all over Europe and Sykes has employed six people.
"Some of my colleagues said what are you doing making money out of research, but I do really believe that with something as important as this, people should have access to the latest genetic technology."
The company is not part of his laboratory and while it makes a profit, Sykes says that is not the motivation.
"It's a revelation that people are so interested in their origins. Why do we care? We have seven women who did exist and nonetheless there are uncertain elements. [His descriptions of the seven in the book] are a literary device. It is fiction but does strike home.
"Before I started, ancestors were a hazy collection of dead people. I never thought of them as individuals. I do want to know what their lives were like and how they compare to our lives. Because we've shown that genetically they were very much the same as we are today and all the DNA in our body came from these individuals. I thought this a powerful and emotional feeling, irrational but powerful."
In his book Sykes recounts the experience of one of his colleagues, Jendayi Serwah, whose parents had arrived in Britain from Jamaica as teenagers.
Their ancestor had been slaves, taken from Africa and sold to plantation owners. As slaves they lost their identity, received European names and any record of their birth, parentage and heritage obliterated.
While she assumed her ancestry was African, Sykes was able to take her DNA and match it to Kenyan Kikuyu.
Sykes writes, "She was literally lost for words. Here at last was the individual proof she had wanted for so long. It was as if the DNA was itself a written document from her ancestors, which in a sense it was; a document that had been handed down one generation at a time, from the woman who had endured and survived the terrible voyage from Africa. A document that could not be obliterated by the plantation owners as it passed unseen and unread for generations. And now in Jendayi, here it was, a perfect copy of the African original preserved in her own body."
What became of Tsar Nicholas, the ruler of imperial Russia, and his family?
In 1991 nine bodies were recovered from shallow graves in birch woods outside Ekaterinburg, in the Russian Urals. Nearby was the site of the house where the Russian royals were reputedly executed in the cellar by their Bolshevik guards. Forensic evidence suggested that the skeletons belonged to the Tsar, the Tsarina, three of their children - Maria, Tatiana and Olga, their doctor Eugeny Botkin and three servants.
Sykes and his colleagues were able to prove via mDNA that there was a family of two adults and three children. The next step was to prove who they were.
After discreet negotiations they were able to collect a blood sample from Prince Philip, the Duke of Edinburgh who has a direct maternal link to the Russian royal family.
Prince Philip's DNA matched that taken from the skeletons. But what of the other two children, Alexei and Anastasia, whose bodies were never found?
Sykes has only been able to disprove the claims of Anastasia pretender Anna Anderson. The theory based on the accounts of some of the guards is that the final two children were put on a pyre and their charred remains lie near the grave of their parents, beyond the ability of even mDNA to prove who they were.