It offers users a chance to see if they are at risk from certain diseases and has a green light to go on sale, after securing a so-called "CE" mark of European quality assurance.

Last year, 23andme agreed to stop selling its DNA test in the United States after the Food and Drug Administration said false positive or false negative results could prompt patients to take "morbidity inducing" actions, like unnecessary surgery.

It is now seeking regulatory approval for the U.S. market.

The firm said it would charge 125 pounds in Britain for its Personal Genome Service (PGS), which provides more than 100 reports on health, traits and ancestry.

Formed in 2006 by Anne Wojcicki, wife of Google co-founder Sergey Brin, 23andme aims to deliver insights about people's genetic heritage from a swab of saliva.

It includes results for genes associated with certain inherited conditions such as cystic fibrosis or sickle cell anaemia, as well as tests for genes that may reveal risk factors for diseases like Alzheimer’s or Parkinson’s.

It also offers a genetic ancestry report, allowing people to trace their family’s genetic roots.

23andme said Britain was a logical market for launch. "The UK is a world leader in genomics and we are very excited to offer a product specifically for UK customers," Wojcicki said in a statement.

But critics said that genetic tests could be misinterpreted and the Department of Health said people should think carefully before using private genomic services.

"This type of test is very open to misunderstanding," Shirley Hodgson, emeritus professor of cancer genetics at St. George's Hospital in London, said.

"The results can indicate very slight alterations of risk for certain traits or diseases which can be misinterpreted unless explained in detail by a medical practitioner who understands such information."

However, Tim Spector, a genetics professors at King's College London, was more relaxed. “I am in favour of any way to get the UK public more involved in science and genetics – and this is a great way to get educated in the power of genetics as well as its limitations," he said. 

(Editing by Jane Merriman)

By Ben Hirschler