NOBEL PRIZE-WINNING scientist James Watson, who helped discover that DNA is a double helix shape, has been stripped of several titles by the lab he once headed.

Watson, who lost his job in 2007 for expressing racist views, had his honorary titles revoked by Cold Spring Harbor Laboratory, which said it was reacting to his remarks in a television documentary aired earlier this month.

In the film, Watson said his views about intelligence and race had not changed since 2007, when he told a magazine that he was “inherently gloomy about the prospect of Africa”.

He claimed that modern social policies were “based on the fact that their intelligence is the same as ours – where all the testing says not really”.

Watson also said that while he hopes everyone is equal, “people who have to deal with black employees find this is not true”.

In this month’s documentary, he said that genes cause a difference on average between black people and white people on IQ tests.

Cold Spring Harbor Laboratory called his latest remarks “reprehensible” and “unsupported by science”, adding that they effectively reversed a written apology and retraction by Watson in 2007.

The New York lab said it had revoked three honorary titles, including chancellor emeritus and honorary trustee.

Watson has long been associated with the lab, becoming its director in 1968, its president in 1994 and its chancellor ten years later, while a school at the lab is named after him.

On Friday, his son Rufus said that his father, who is 90 years old, was in a nursing home following a car crash in October, and that his awareness of his surroundings is “very minimal”.

“My dad’s statements might make him out to be a bigot and discriminatory,” he said, adding that this was not true.

“They just represent his rather narrow interpretation of genetic destiny. My dad had made the lab his life, and yet now the lab considers him a liability,” he said.

Watson shared the 1962 Nobel Prize with collaborator Francis Crick and scientist Maurice Wilkins for discovering in 1953 that DNA was a double helix, shaped like a long, gently twisting ladder.

The breakthrough was key to determining how genetic material works.

The double helix became a widely recognized symbol of science, and Watson himself became famous far beyond scientific circles.