Expensive tests claiming to trace person's ancestry 'as dubious as astrology', warn scientists Rubbished: Tests that claim to trace a person's ancestry from a DNA sample are no more than 'genetic astrology', scientists have said. Comedian Eddie Izzard has made a TV programme about tracing his family back Expensive tests that claim to trace a person's ancestry from a DNA sample are no more than "genetic astrology," scientists said last night. They warned general information is being presented as personal, and claims someone is related to a famous figure such as Cleopatra are often no less likely to be true for a random passer-by than for the subject of the test. Numerous companies have sprung up which charge £30 to £300 to trace a person's past from a saliva sample. Business is booming, with some valued at £1billion. Actor Tom Conti recently spoke of his shock on discovering he is related to Napoleon. And comedian Eddie Izzard has made a TV programme about tracing his family back 10,000 generations. A leaflet by charity Sense About Science says such claims should be taken with a large pinch of salt. It explains the DNA tests used were designed to look at a whole population, not individuals. This means results are vague at best, and may be plain wrong. The charity says that our most recent common ancestor dates back just 3,500 years, meaning many of us will find the same colourful characters in our past. The leaflet says: "A company might tell you you are related to the Queen of Sheba. The short answer is yes, you probably are. We could say this for many people alive today. We are all related, it's a matter of degree. Steve Jones, emeritus professor of genetics at University College London, said: "In a long trudge through history, two parents, four grandparents and so on, very soon everyone runs out of ancestors and has to share them. As a result, almost every Briton is a descendent of Viking hordes, Roman legions, African migrants, Indian Brahmins, or anyone else they fancy. Booming: Numerous companies have sprung up which charge £30 to £300 to trace a person's past from a saliva sample. This is a file picture And despite claims to the contrary, the tests can't pinpoint which part of the world a person's ancestors came from - or how their forbearers moved across the globe. Professor David Balding, of also of UCL, advises that those interested in learning about their family tree should follow a more traditional, and less expensive, method of research, such as unearthing written information from boxes and trunks in their attic and scouring church records. He said: "Be very wary about the claims of DNA companies because they are prone to exaggeration." Mark Thomas, professor of evolutionary genetics at UCL, said: "Ancestry is complicated and very messy. Genetics is even messier. The idea that we can read our ancestry directly from our genes is absurd. This is business, and the business is genetic astrology.