JAMES WATSON, the DNA pioneer who claimed Africans are less intelligent than whites, has been found to have 16 times more genes of black origin than the average white European.

An analysis of his genome shows that 16% of his genes are likely to have come from a black ancestor of African descent. By contrast, most people of European descent would have no more than 1%.

The study was made possible when he allowed his genome - the map of all his genes - to be published on the internet in the interests of science.

“This level is what you would expect in someone who had a great-grandparent who was African,” said Kari Stefansson of deCODE Genetics, whose company carried out the analysis. “It was very surprising to get this result for Jim.”

Watson won the Nobel prize, with Francis Crick and Maurice Wilkins, after working out the structure of DNA in 1953. However, he provoked an outcry earlier this year when he suggested black people were genetically less intelligent than whites.

This weekend his critics savoured the wry twist of fate. Sir John Sulston, the Nobel laureate who helped lead the consortium that decoded the human genome, said the discovery was ironic in view of Watson’s opinions on race. “I never did agree with Watson’s remarks,” he said. “We do not understand enough about intelligence to generalise about race.”

The backlash against Watson forced him to step down as chancellor of Cold Spring Harbor Laboratory, New York state, after 39 years at the helm. He had said he was “inherently gloomy about the prospects for Africa” because “all our social policies are based on the fact that their intelligence is the same as ours - whereas all the testing says not really”.

The analysis by deCODE Genetics, an Icelandic company, also shows a further 9% of Watson’s genes are likely to have come from an ancestor of Asian descent. Watson was not available for comment.

James Watson: genetic risk to diseases compared with other people of European ancestry

- Age-related macular degeneration (blindness) - 20% less than average

- Asthma - 31% less than average

- Breast cancer - 1.45 times greater than average

- Coeliac disease - 66% less than average

- Colon (bowel) cancer - 16% greater than average

- Glaucoma - 1.42 rimes greater than average

- Inflammatory bowel disease - 31% less than average

- Multiple sclerosis - 29% greater than average

- Heart attack - 33% less than average

- Obesity - 5% greater than average

- Prostate cancer - 1.02 times greater than average

- Psoriasis - 31% less than average

- Restless leg - 29% less than average

- Rheumatoid arthritis - 20% greater than average

- Type 1 diabetes - 65% less than average

- Type 2 diabetes - 33% greater than average

Results are calculated by comparing one person's genetic sequence to the sequences of other participants in studies published in world literature on genetic risk for disease

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