James Watson.
Publié le 06/12/2021
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I
INTRODUCTION
James Watson, born in 1928, American molecular biologist and cowinner of the 1962 Nobel Prize in physiology or medicine. Watson shared the prize with British
biophysicists Francis Crick and Maurice Wilkins for their discoveries about the structure of deoxyribonucleic acid (DNA), the molecule that contains the hereditary
information for cells. Watson was also instrumental in establishing the Human Genome Project, the international scientific collaboration that identified the complete
genetic blueprint of humans in 2003.
II
EDUCATION AND EARLY RESEARCH
James Dewey Watson was born in Chicago, Illinois. At the age of 12 he starred on the Quiz Kids, a popular network radio show that challenged precocious youngsters to
answer tough questions. At the age of 15 he enrolled at the University of Chicago. He shared a love of birds with his father and studied natural sciences and zoology,
including ornithology.
After graduating in 1947, he went to Indiana University for graduate studies (after the California Institute of Technology and Harvard University had both turned him
down). He originally intended to pursue a graduate degree in ornithology. But after reading What is Life? (1944), the influential book on genes and heredity by Austrian
physicist and Nobel laureate Erwin Schrödinger, Watson grew increasingly interested in the field of genetics. At Indiana he pursued his graduate studies in genetics
under two Nobel laureates: American geneticist Hermann Muller and Italian-born American physician-biologist Salvador Luria. Luria was one of the founders of the
Phage Group, an informal group of scientists at different universities who worked together on bacteriophages, viruses that are parasites of bacteria.
Watson worked on the effect of X rays on bacteriophage replication for his doctoral thesis, which he received in 1950. On Luria's advice, he traveled to Europe for his
postdoctoral studies. From September 1950 to September 1951 he studied DNA in bacteriophages in Copenhagen, Denmark, while on a fellowship from the National
Research Council.
In May 1951 Watson attended a symposium where he met Wilkins of King's College, London. Wilkins showed Watson an X-ray diffraction picture of DNA. X-ray
diffraction provides X-ray patterns of a molecule's chemical structure. Wilkins's project stimulated Watson to change the direction of his research toward the structural
chemistry of deoxyribonucleic acid. Watson believed that it would be possible to determine the structure of DNA from the analysis of X-ray diffraction patterns, and that
knowing the structure of DNA would be the key to understanding genes.
To follow his research interests, in 1951 Watson transferred to the Cavendish Laboratory at the University of Cambridge, one of the world's leading centers of X-ray
diffraction.
III
WATSON TEAMS WITH CRICK
At Cambridge, Watson met Francis Crick, who was working on his doctoral thesis on protein structure. Both men were keenly interested in studying the structure of DNA
and from 1951 to 1953, Watson and Crick collaborated on their DNA studies, while continuing independent research.
To help them in their research, the pair asked Wilkins and British physical chemist Rosalind Franklin at King's College, London, to perform X-ray diffraction analysis of
the DNA molecule. After many tries, Watson and Crick used the X-ray diffraction patterns created by Franklin to develop a model for the three-dimensional structure of
DNA. The model depicted DNA as two complementary strands twisted into a double helix. The famous photograph of the two men next to their double helix model has
become an icon of molecular biology.
Watson and Crick broke the news of their discovery in the British science journal Nature on April 25, 1953. The Watson-Crick model, as it became known, was of
momentous importance in biology. The model enabled scientists to understand and describe living things for the first time in terms of the structure and interaction of
molecules. American biochemist Arthur Kornberg provided experimental proof for their model in 1956. The discovery of the structure of DNA set the stage for rapid
advances in molecular biology over the next 50 years.
IV
LATER RESEARCH
In the summer of 1953 Watson returned to the United States, spending the summer at Cold Spring Harbor Laboratory of Quantitative Biology, New York, with Germanborn American biologist Max Delbrück before becoming a research fellow at the California Institute of Technology. There he used X-ray diffraction to study the structure
of ribonucleic acid (RNA), a molecule important in the manufacturing of proteins. He spent 1955 studying virus structures with Crick at Cambridge University before
accepting a position in the biology department at Harvard University. At Harvard, Watson taught molecular biology and continued his research in the role of RNA in
protein synthesis.
In 1968 Watson became director of the Cold Spring Harbor Laboratory, while still at Harvard. In 1976 he left Harvard to become full-time director of Cold Spring Harbor
Laboratory. Under his direction, the laboratory became a leader in the field of oncogenes (cancer genes) and the molecular basis of cancer.
From 1988 to 1992 Watson directed the Human Genome Project at the National Institutes of Health. In the early stages of this project, Watson was instrumental in
convincing the U.S. government to provide funding and he spearheaded the collaboration of governments and leading scientists from around the world. His concern
about the ethics of science and the general public's misunderstanding of scientific issues led him to establish the Ethical, Legal, and Social Issues Program as part of the
work of the Human Genome Project.
V
PUBLICATIONS AND AWARDS
While teaching at Harvard, Watson wrote an influential textbook, The Molecular Biology of the Gene (1965), which set new standards in its field. Later he provided his
own account of the discovery of the structure of DNA in The Double Helix (1968). A new departure in scientific autobiography and an international bestseller, this quirky
account of scientific research and bald discussion of colleagues both shocked and delighted readers.
In addition to the Nobel Prize, Watson has received many honors, including the Lasker Prize (1960), the John J. Carty Gold Medal of the National Academy of Sciences
(1971), the Presidential Medal of Freedom (1977), and the National Medal of Science, awarded by President Bill Clinton in 1997.
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