Matthew Stanley Meselson (born May 24, 1930) is a geneticist and molecular biologist currently at Harvard University, known for his demonstration, with Franklin Stahl, of semi-conservative DNA replication.
After completing his Ph.D under Linus Pauling at the California Institute of Technology, Meselson became a Professor at Harvard University in 1960, where he has remained, today, as Thomas Dudley Cabot Professor of the Natural Sciences.
In the famous Meselson–Stahl experiment of 1958 he and Frank Stahl demonstrated through nitrogen isotope labeling that DNA is replicated semi-conservatively.
In addition, Meselson, François Jacob, and Sydney Brenner discovered the existence of messenger RNA in 1961.
Meselson has investigated DNA repair in cells and how cells recognize and destroy foreign DNA, and, with Werner Arber, was responsible for the discovery of restriction enzymes.
Since 1963 he has been interested in chemical and biological defense and arms control, has served as a consultant on this subject to various government agencies.
Meselson worked with Henry Kissinger under the Nixon administration to convince President Richard Nixon to renounce biological weapons, suspend chemical weapons production, and support an international treaty prohibiting the acquisition of biological agents for hostile purposes, which in 1972 became known as the Biological Weapons Convention.
Meselson has received the Award in Molecular Biology from the National Academy of Sciences, the Public Service Award of the Federation of American Scientists, the Presidential Award of the New York Academy of Sciences, the 1995 Thomas Hunt Morgan Medal of the Genetics Society of America, as well as the Lasker Award for Special Achievement in Medical Science.
His laboratory at Harvard currently investigates the biological and evolutionary nature of sexual reproduction, genetic recombination, and aging.
Many of his past students are notable biologists, including Nobel Laureate Sidney Altman, as well as Mark Ptashne, Susan Lindquist, Stephen F.