Walter Gilbert developed a technique of using gel electrophoresis to read the nucleotide sequences of DNA segments.
Walter Gilbert was born on March 21, 1932 in Boston, Massachusetts. His father, Richard V. Gilbert, was an economist at that time at Harvard University. He worked for the Office of Price Administration during the Second World War and later headed up a planning group advising the Pakistani government. His mother, Emma Cohen, was a child psychologist, who practiced giving intelligence tests to Walter and his younger sister.
Since childhood, Gilbert always had an interest in science, in those years' mineralogy and astronomy. He became more interested in inorganic chemistry while he was in the high school. He spent his first graduate year at Harvard, and then went to the University of Cambridge for two years, where he received his doctorate degree in 1957. His thesis supervisor was Abdus Salam and he worked on dispersion relations for elementary particle scattering: an effort to use a notion of causality, formulated as a mathematical property of analyticity of the scattering amplitude, to predict some aspects of the interaction of elementary particles.
He met Jim Watson during this period. He returned to Harvard and, after a postdoctoral year and a year as Julian Schwinger's assistant, became an assistant professor of Physics. During the late fifties and early sixties, he taught a wide range of courses in theoretical physics and worked with graduate students on problems in theory. However, after a few years his interests shifted from the mathematical formulations of theoretical physics to an experimental field.
Secrets behind RNA and DNA
In the summer of 1960, Jim Watson told him about an experiment that he and Francois Gros and his students were working on. Gilbert found the ideas exciting and joined in for the summer. They were trying to identify messenger RNA, a short-lived RNA copy of a DNA gene, which serves as a carrier of information from the genome to the ribosomes, the factories that make proteins. After each messenger is used a few times to dictate the structure of a protein, it is broken down and recycled to make other messenger RNA molecules. The experiments sought a fleeting new component that they finally managed to pin down. He found the experimental work exciting and have continued research in molecular biology ever since. After a year of work on messenger RNA, he returned briefly to physics then came back to biology to study how proteins are synthesized. He showed that a single messenger molecule can service many ribosomes at once and that the growing polypeptide chain always remains attached to a transfer RNA molecule. This last discovery illuminated the mechanism of protein synthesis: the protein chain is transferred in turn from one amino-acid-bearing transfer RNA to another as it grows, their order dictated by messenger RNA and ultimately by the genetic code on the DNA. Walter Gilbert's work with RNA and DNA fetched him a Nobel Prize.
In the 1970s, he developed a technique of using gel electrophoresis to read the nucleotide sequences of DNA segments. In 1979, he co-founded Biogen which is a commercial genetic-engineering research corporation. Gilbert resigned from Biogen in 1985 and became a chief proponent of the Human Genome Project which is a government-funded effort to compile a complete map of the gene sequences in human DNA.