A Nobel Prize-winning American scientist who co-discovered DNA has been stripped of his honorary titles at the laboratory he once led. The move came after he repeated racist comments in a documentary.James Watson, who discovered the double-helix structure of the DNA alongside Francis Crick in the 1950s based on the work of British chemist Rosaling Franklin, said in a PBS film that genes cause a difference in intelligence between white and black people in IQ tests.Cold Spring Harbor Laboratory (CSHL) labelled the nonagenarian scientist's comments 'reprehensible', reported CNN.James Watson had been the director of CSHL from 1968 to 1993.The laboratory said that it "unequivocally rejects the unsubstantiated and reckless personal opinions Dr. James D. Watson expressed," noting the statements were "reprehensible [and] unsupported by science."The statement further added that it condemns the misuse of science to justify prejudice.CNN further wrote that Watson had in a previous occasion told .