Watson, James

Early Life and Training

Watson was born April 6, 1928, in Chicago, Illinois. He showed his brilliance early, finishing high school in two years and appearing as one of the original "Quiz Kids," on a popular 1940s radio show of the same name. He was graduated from the University of Chicago in 1947 with a B.S. in zoology, reflecting an early love of birds. He did his doctoral work at Indiana University in genetics, and earned a Ph.D. in 1950. He was drawn to Indiana by the chance to work with Hermann Joseph Muller, who had been one of Thomas Hunt Morgan's associates in the famous "fly room" at Columbia University, and who had received a Nobel Prize for his discoveries in genetics. Watson's thesis adviser and principal mentor was Salvador Luria, who, along with Max Delbrück, had established bacterial genetics as the experimental system in which most of the major discoveries in molecular biology were to be made. Watson's thesis was on the effect of X rays on the multiplication of a bacterial virus, called phage.

Watson continued to study phage as a postdoctoral student in Copenhagen, Denmark where he worked from 1950 to 1951. While there, he met Maurice Wilkins, and for the first time saw the X-ray diffraction images generated in Wilkins's lab by Rosalind Franklin. Watson quickly decided to turn his attention to discovering the structure of important biological molecules, including DNA and proteins. By that time, DNA had been shown to be the genetic molecule, and it was believed that it somehow carried the instructions for making proteins, which actually perform most of the work in a cell.

The Structure of DNA

Luria arranged for Watson to continue his work at the Cavendish Laboratory in Cambridge, England, which was a center for the study of biomolecular structure, and Watson arrived there in late 1951. At the Cavendish, he met Francis Crick, who, after training in physics, had turned his attention to similar structural questions. The two hit it off, and began collaborating on the structure of DNA.

Watson and Crick approached the problem by building models of the four nucleotides known to make up DNA. Each was composed of a sugar called deoxyribose, a phosphate group, and one of four bases, called ade-nine, thymine, cytosine, and guanine. They knew the sugars and phosphates alternated to form a chain, with the bases projecting off to the side. The X-ray images they had seen suggested the structure was a helix, and offered more information about dimensions as well. They also knew that the biochemist Erwin Chargaff had discovered that the amounts of adenine and thymine in a cell's DNA were equal, as were the amounts of cytosine and guanine.

After several failed attempts, more analysis of the X-ray images, and a fortuitous conversation with a biochemist who corrected one of their hypothesized base structures, they developed the correct model. The helix is formed from two opposing strands of sugar phosphates, while the bases project into the center. Weak bonding (called hydrogen bonding) between bases holds them together. The key, as Watson and Crick discovered, was that the hydrogen bonds work best when adenine pairs with thymine, and guanine with cytosine, thus explaining Chargaff's ratios. The structure immediately suggested a replication mechanism, in which each side serves as the template for the formation of a new copy of the opposing side, and they speculated, correctly, that the sequence of the bases was a code for the sequence of amino acids in proteins. They published their results in 1953, and received the Nobel Prize for physiology and medicine for it 1962, along with Wilkins (Franklin by then had died, and was therefore ineligible for the prize).

Later Accomplishments

Watson remained active in the study of DNA and RNA for a number of years after the publication of the DNA structure. He joined the faculty of Harvard University in 1955, and remained there until 1976. During this time, he wrote an influential textbook, Molecular Biology of the Gene, and an enormously popular (and colorful) account of his and Crick's discovery, called The Double Helix.

In 1968 Watson became the director of the Cold Spring Harbor Laboratory on Long Island, New York, and he became president of the laboratory in 1994, a position he continues to hold. Watson revitalized this laboratory, helping it become one of the premier genetics research institutions in the world. His organizational drive was also called upon in 1988, when he spearheaded the launch of the U.S. Human Genome Project, dedicated to determining the sequence of the entire three billion bases in the genome. He headed the project from 1988 to 1992.

Throughout his career, Watson has invariably been described as "brash," reflecting his capacity to take on big projects and big ideas, and his enthusiasm for making daring, occasionally outrageous predictions about the causes of an unexplained phenomenon or the direction science will take. Explaining this tendency in relation to his work on DNA, Watson wrote, "A potential key to the secret of life was impossible to push out of my mind. It was certainly better to imagine myself becoming famous than maturing into a stifled academic who had never risked a thought."

SEE ALSO CRICK, FRANCIS; DELBRück, MAX; DNA; DNA STRUCTURE AND FUNCTION, HISTORY; MORGAN, THOMAS HUNT; MULLER, HERMANN; NUCLEOTIDE.

Richard Robinson

Bibliography

Judson, Horace F. The Eight Days of Creation, expanded edition. Cold Spring Harbor, NY: Cold Spring Harbor Press, 1996.

Watson, James. The Double Helix: A Personal Account of the Discovery of the Structure of DNA. New York: New American Library, 1991.

———. Genes, Girls, and Gamow: After the Double Helix. New York: Knopf, 2002.

Internet Resource

"Biographical Sketch of James Dewey Watson." <http://nucleus.cshl.org/CSHLlib/archives/jdwbio.htm>.