James Dewey Watson is an American molecular biologist, geneticist and zoologist, best known as one of the co-discoverers of the structure of DNA in 1953. He was born on April 6, 1928 in Chicago, Illinois, United States. Watson earned degrees at the University of Chicago (B.S., 1947) and Indiana University (Ph.D., 1950). Following a post-doctoral year at Copenhagen University with Herman Kalckar and Ole Maaloe, Watson next worked at the University of Cambridge's Cavendish Laboratory in England. From 1953 to 1955, Watson was at the California Institute of Technology as Senior Research Fellow in Biology. There he collaborated with Alexander Rich in X-ray diffraction studies of RNA. In 1955-1956 he was back in the Cavendish, again working with Crick. During this visit they published several papers on the general principles of virus construction.     In 2005, he received the Othmer Gold Medal.

From September 1950 to September 1951 he spent his first postdoctoral year in Copenhagen as a Merck Fellow of the National Research Council. Part of the year was spent with the biochemist Herman Kalckar, the remainder with the microbiologist Ole Maaløe. Again he worked with bacterial viruses, attempting to study the fate of DNA of infecting virus particles. During the spring of 1951, he went with Kalckar to the Zoological Station at Naples. There at a Symposium, late in May, he met Maurice Wilkins and saw for the first time the X-ray diffraction pattern of crystalline DNA. This greatly stimulated him to change the direction of his research toward the structural chemistry of nucleic acids and proteins. Fortunately this proved possible when Luria, in early August 1951, arranged with John Kendrew for him to work at the Cavendish Laboratory, where he started work in early October 1951.