James Watson (born 1928), US molecular biologist and co-discoverer of the structure of DNA (deoxyribonucleic acid). Watson worked with Francis Crick at the Cavendish Laboratory, Cambridge, UK, in 1951. Their work on DNA was performed with a knowledge of Chargaff's ratios of the bases in DNA and access to the X-ray crystallography of Maurice Wilkins and Rosalind Franklin at King's College London. Combining this knowledge led to the deduction that DNA exists as a double helix. Watson, Crick and Wilkins shared the 1962 Nobel Prize for Physiology or Medicine, Franklin having died in 1958. Photographed in the Jones Laboratory at Cold Spring Harbor, New York, USA, where Watson was Director.