Born May 24, 1930 in Denver, Colorado, Matthew Meselson received the Ph.B. degree in liberal arts from the University of Chicago in 1951 and the Ph.D. in chemistry from the California Institute of Technology in 1957. He was a Research Fellow and Assistant Professor of Physical Chemistry at CalTech until he joined the Harvard faculty in 1960.
Professor Meselson has conducted research mainly in molecular biology and genetics. While at CalTech, he invented an important ultracentrifugal method, equilibrium density-gradient centrifugation, for analyzing the densities of giant molecules. He and his colleague Franklin Stahl then used it to show that DNA molecules replicate semi-conservatively in dividing cells and, with a student, to show the molecular conservation of ribosomal RNA. Together with Jean Weigle, he employed the density gradient method to show that genetic recombination results from the breakage and joining of DNA molecules and, with Sydney Brenner and Francois Jacob, to demonstrate the existence of messenger RNA.
After moving to Harvard, Meselson and his students demonstrated the enzymatic basis of host-controlled restriction of DNA and predicted and then discovered methyl-directed repair of mismatched DNA. In 1989, he initiated experiments directed at the problem of why asexual species almost invariably suffer early extinction. He and his students recently showed that bdelloid rotifers, a large and ancient group of invertebrates in which males and meiosis have never been detected, nevertheless do exchange homologous DNA within populations, thereby resolving the principal challenge to the generalization that such exchange is essential to long-term evolutionary success. He and his colleagues also discovered bdelloid rotifers to be far more resistant to ionizing radiation than any other animal species for which there is relevant information and to be subject to massive horizontal transfer of genes from unrelated species, including bacteria, plants and fungi. Working together with colleagues in France, he recently found that bdelloid radiation resistance is associated with an extraordinary degree of protection against radiation-induced oxidative damage, as manifested by measurements of protein carbonylation. Most recently Professor Meselson has begun to develop bdelloid rotifers as a particularly favorable model organism for investigating the causes and control of aging.
Since 1963 when he served as a full-time summer consultant in the US Arms Control and Disarmament Agency in Washington D.C., Professor Meselson has had an interest in arms control aspects of biological and chemical weapons and in anti-CBW protection, subjects on which he has acted as consultant to various government agencies. During August and September 1970, Meselson led a team in the Republic of Vietnam in a pilot study of the ecological and health effects of the military use of herbicides, on behalf of the American Association for the Advancement of Science and, upon returning to Cambridge he and his students developed an advanced mass-spectrometric method for the analysis of the toxic herbicide contaminant TCDD and applied it to environmental and biomedical samples from Vietnam and the US. In 1983, Professor Meselson and Thomas Seeley, then at Yale, went to Thailand to conduct a field study of the so-called "yellow rain", initially feared to be a toxic weapon but shown by Meselson and his colleagues to be non-toxic feces dropped by large swarms of the giant Asian honeybee Apis dorsata. More recently, in 2002 and again in 2003, Meselson led a team to Sverdlovsk (now Yeketerinburg), Russia to investigate the major outbreak of human and animal anthrax that occurred there in 1979 and had been a subject of international dispute, conclusively demonstrating that it was caused by an airborn release of the pathogen from a closed military biological facility located in the city.
Professor Meselson is a member of the U.S. National Academy of Sciences, the Académie des Sciences, the Royal Society and the Russian Academy of Sciences and has received numerous awards and honors in the field of science and in public affairs. He has served on the Council of the National Academy of Sciences, the Council of the Smithsonian Institution, the Arms Control and Non-Proliferation Advisory Board to the U.S. Secretary of State and the Committee on International Security and Arms Control of the U.S. National Academy of Sciences. He is past President of the Federation of American Scientists, and presently is Co-director of the Harvard Sussex Program on Chemical and Biological Weapons, a member of the Steering Committee of the Pugwash Study Group on the Implementation of the Chemical and Biological Weapons Conventions and a member of the Board of Directors of the Belfer Center for Science and International Affairs at the John F. Kennedy School of Government at Harvard University.