James Watson and Francis Crick with their DNA model at the Cavendish Laboratories in 1953. Photograph by C. Barrington Brown. Courtesy C. Barrington Brown. To request permission to use this photo, please visit the Science Photo Library Web site at www.sciencephoto.com. James Watson (1928– ) James Watson, a Chicago native, was a child prodigy who entered college at the age of 15. By 23 he was a postdoctoral fellow at the University of Copenhagen studying genetics. It was there that he heard Maurice Wilkins of King’s College give a talk about investigations into the molecular structure of DNA. Watson was hooked, and he moved to Cambridge University’s Cavendish Laboratory to study DNA’s structure. Watson worked well there with Francis Crick, and the two began using three-dimensional molecular models to test structural ideas. In 1953 Wilkins showed Watson and Crick X-ray crystallographic images of DNA taken by Wilkins’s coworker Rosalind Franklin. On the basis of these images—which had been shown without Franklin’s knowledge—Watson and Crick worked out a double-helical structural model within a few weeks. For this Watson, Crick, and Wilkins were awarded the Nobel Prize in physiology or medicine in 1962. In addition to his work on DNA, Watson also discovered the molecular structure of the tobacco mosaic virus and helped uncover the role of messenger RNA in protein synthesis. Watson described the discovery of DNA in his highly popular book The Double Helix, though the book has been criticized for downplaying Franklin’s role in the discovery.