What does it mean to be British? With the 200th anniversary of the abolition of the slave trade marked tomorrow, new techniques of DNA testing are revealing how one of Britain’s cruellest contributions to world history is embedded not only in our society but in our genes.

Tim Campbell, the winner of the BBC reality show The Apprentice in 2005, who left his job with Amstrad boss Sir Alan Sugar this week, never knew his family background beyond a maternal grandmother in Jamaica. Then he was approached by the Dana Centre, a branch of the Science Museum, and asked if he would like to participate in a debate to be held next week, which will explore how black people living in Britain can trace their roots to Africa. A genetic test to trace his ancestors came as part of the offer: “It was the best Christmas present I could have had,” he says.

The test revealed that his ancestors were Bantu-speakers from southern Africa, and almost certainly deported as slaves. “A lot of people are happy to live in ignorance about their ancestry, which I quite understand, but I needed to know more about what my community contributed before and after the slave trade,” he says. “It’s about self-esteem, and I think it’s a similar feeling to the one people have when they’ve been adopted. The more information you have, the more confident you can feel about yourself.”

The same gene-testing techniques are also revealing surprising things about apparently white Britons. Many are descended from black slaves or from black people who have come to Britain over the past 2,000 years. Earlier this year, for example, a Leicester University genetics study, funded by the Wellcome Trust, uncovered that a set of typically West or North African genes had been found in seven white Englishmen sharing the same rare surname: Revis. The name has carried with it, down the male line, genetic material of African origin. This may have arrived in Britain any time between the Roman Empire, which brought African soldiers to Britain, to the 18th century, when the slave trade was in full flow.

“It was a complete surprise when they told me the results,” says John Revis, 75, from Leicester. “Especially since the boys in the family have nearly always been blond-haired and blue-eyed.”

This isn’t a one-off. According to Professor Elizabeth Anionwu, the head of the Mary Seacole Centre for Nursing Practice, and the instigator of the Dana event, genetics promotes greater understanding of the legacy of slavery and proves that many Britons have black ancestry. Her work as a pioneer in screening for sickle cell anaemia — caused by a genetic susceptibility found mainly in people of African and Caribbean descent — has made clear to her that many ostensibly white babies, with white parents, are carrying the sickle cell gene. Exactly how many, she says, will be revealed only once screening is rolled out for all babies in the UK this summer.

The scale of ethnic mixing over centuries is just beginning to emerge as genetic testing is perfected. Dr Mark Thomas, from the Centre for Genetic Anthropology at University College London, believes that you need go back only ten generations (250 years) to find a “nonEnglish” ancestor for everyone in England. “It’s the law of averages: the number of our ancestors doubles with every generation.”And while much of the mixing occurred outside slavery, what occurred during that period and later, after slaves became emancipated, can be particularly emotive. Between 1560 and 1807 up to 28 million Africans were enslaved by European powers. Britain sent most slaves to its colonies, but a few remained here as personal servants. By the end of the 18th century there were 20,000 black people in Britain.

Cedric Barber, 58, an ostensibly white financial adviser from Stoke-on-Trent, is the direct descendant of a famous slave: Dr Samuel Johnson’s black manservant Francis Barber (see panel, right), who helped to compile the great man’s dictionary. For Barber, as for many white people with slave ancestors, the discovery of mixed-race ancestry proved life-enhancing. But for black people, genetic evidence of ethnic mixing can have disturbing connotations.

Dr Peter Forster, a geneticist from the University of East Anglia, says that it is very common to find genetic material characteristic of white Europeans in samples provided by black British people. All the evidence is that this is the result of white slave owners having sexual intercourse with their female black slaves. “I’d say that for every Afro-Caribbean living in the UK, there’s a 25 per cent chance that their Y (male) chromosome DNA will have come from a slave owner,” he says.

The techniques that can be used to trace ethnic origins have been perfected and marketed only in the past decade. Dr Forster runs a company, www.rootsforreal.com, that allows people to trace their ancestry to before their great-great-grandparents, a common limit of paperwork searches. By using a saliva sample, Dr Forster can obtain samples of DNA from our cells’ mitochondria (mtDNA), which is passed unaltered from mother to child down the generations, and from the Y chromosome, which is passed down from fathers to sons and reveals the male lineage. The sequence of nucleotides, the structural units of DNA, on these samples is fed into a world database of 40,000 DNA samples, pinpointing those areas of the world where there is an identical or close match, and therefore people (though kept anonymous) who are, in effect, your very distant cousins. This can provide vital clues to where your lineage originated up to 2,000 years ago.

Dr Thomas suggests that there may be a margin of error in such testing because populations are mobile and DNA databases are partial. But Dr Forster says the service is proving particularly popular for British black people, who want to trace where they originated preslavery. The problem for British people who originate in the Caribbean, one of the main destinations for slaves from Africa, is that their slave-ancestors’ names were removed, their families broken up, and their natural language lost. Everything that allowed them to trace their family disappeared.

The DNA tests that Dr Forster conducted on Tim Campbell’s DNA revealed an exact mitochondrial DNA match with that of four other people on the database — all of whom were Bantu speakers from tribes in Angola and Mozambique — and a Y chromosome match with a Bantu speaker from South Africa. New research indicates that far more slaves came to Britain and America from these southern areas of Africa than was originally thought. “I suppose it doesn’t tell me anything specific about my ancestors,” says Campbell, “ but it gives me a point of reference geographically.” He aims to follow the trail forward from the southern African ports that conveyed slaves, to try to find out where they went. There are detailed accounts of slave movements in the British Library.

What Campbell communicates so well is that DNA testing is putting the slave trade in a completely different perspective, both for the white and black communities in the UK. It is making us reexamine history not on the basis of prejudice and assumption, but on fact.

“It’s such a big bit of history that you have to hit it hard, and go through it,” says Campbell. “I want the slave trade to be a chapter in my community’s history, not the whole book.”

Tracing Your Ancestry will be held at the Science Museum’s Dana Centre, London SW7, next Thursday. The event is free but places should be booked; phone 020-7942 4040. Visit www.danacentre.org.uk for details

Descended from a very special slave

Cedric Barber, a financial adviser from Stoke-on-Trent, is a direct descendant of Francis Barber, the Afro-Caribbean servant of Dr Samuel Johnson. Francis Barber helped the great lexicographer to prepare his English dictionary between 1747 and 1755.

Cedric had always known vaguely about his family ancestry, and noted his father’s permanently tanned complexion and dark wavy hair (“I thought it was because he’d been in the Tropics during the war”) but only when he started researching his family history through the internet two years ago, at the age of 56, did he realise that he was a direct descendant. He is his great-great-great-great-grandson, with every Barber male descendant having married a white European wife. He visited Lichfield, Dr Johnson’s birthplace, and was hailed as a celebrity. And from then on his newly embraced family background has completely changed his life.

“Francis was born to slavery in Jamaica but in the end Dr Johnson, who was opposed to slavery, left him virtually his whole estate,” says Cedric. “Having ignored my family history for most of my life, I now find the whole subject of slavery makes me very emotional. And today, when I hear stories about people from the Caribbean staying over here illegally, it makes me angry — to think that we took these people from their homes in Africa, sent them to Jamaica, and then in the 1950s asked them to come over here to do lousy jobs we didn’t want to do. What right do we have to ship them around again?

“In my teens I was a member of a boxing club, with black people, and I thought they were just different, and led different lives. But now I have many black friends, and I feel I want that fellowship with them more.”

FREE GENE TEST

The Dana Centre and Body&Soul are offering one reader the chance to have their genetic ancestry traced. Send your name, address and contact number to body&soul@thetimes.co.uk or Body & Soul, The Times, 1 Pennington Street, London E98 1TT, and explain in fewer than 100 words why you’d like your DNA traced.

TERMS AND CONDITIONS

1. Entrants must be 18 or over.
2. All entries must be received by 30 April 2007.
3. The Times Body&Soul and the Dana Centre will select the winner on the basis of the most compelling entry. The winner will be notified by 1 June 2007. The judges' decision is final and no correspondence will be entered into.
4. Only one entry per person.
5. The prize is a mtDNA test and a Y-DNA test conducted for the winner by Roots for Real to the value of £300 (incl. post, packaging and VAT) , is nontransferable and cannot be exchanged for cash.
6. The winner agrees to take part in a possible follow-up story.
7. The test will provide geographic information on ancestry of an individual and Times Newspapers Limited and Science Museum’s Dana Centre accepts no liability for the results.
8. All tests are subject to Roots for Real’s terms and conditions and privacy policy.
9. Prize must be taken by 31st December 2007.
10. Competition rules published in The Times form part of these terms and conditions

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