James Watson, the geneticist credited with the co-discovery of the structure of DNA, has abandoned a book tour in Britain after suggesting that he thinks black people may be less intelligent than whites.

In an interview with the London-based Sunday Times, published on 14 October, the 79-year-old said he was ?inherently gloomy about the prospect of 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?.

After the comments were picked up by other media on 17 October, Cold Spring Harbor Laboratory in Long Island, New York, announced that it was suspending Watson from 'administrative duties' as chancellor of the Watson School of Biological Sciences there.

Watson said he regretted his comments, but criticism from senior US colleagues was unsparing. ?He has failed us in the worst possible way,? said Henry Kelly, president of the Federation of American Scientists. ?It is a sad and revolting way to end a remarkable career.?