James D. Watson, whose co-discovery of the twisted-ladder structure of DNA in 1953 helped light the long fuse on a revolution in medicine, crimefighting, genealogy and ethics, has died. He was 97. The breakthrough — made when the brash, Chicago-born Watson was just 24 — turned him into a hallowed figure in the world of science for decades. But near the end of his life, he faced condemnation and professional censure for offensive remarks, including saying Black people are less intelligent a...