Getty ImagesIn February 1953, two men walked into a pub in Cambridge and announced they had found "the secret of life". It was not an idle boast.One was James Watson, an American biologist from the Cavendish laboratory; the other was his British research partner, Francis Crick. Their discovery - of the structure and function of deoxyribonucleic acid or DNA - ranks alongside those of Mendel and Darwin in its significance to modern science.The full Promethean power of their achievement would slowly emerge over decades of research by fellow...