Hermann Joseph Muller

muller Hermann Muller, the father of radiation genetics, began his career with T.H. Morgan studying mutations in fruit flies (Drosophila). Muller grew impatient with the mutation rate in Drosophila and was the first to increase the mutation rate using heat. Still not satisfied, he irradiated the flies with 50 kilovolt X rays (ca. November 1926) that resulted in an even greater incidence of mutations. In doing so, he was the first to demonstrate radiation-induced genetic alterations! Moreover, he did so in a quantitative manner that determined the mutation frequency. Nevertheless, it took nearly two decades for this work to be recognized with the Nobel Prize. The delay was in large part due to his left-wing politics, his controversial views on eugenics and his often unpopular opinions about the hazards of radiation. In 1931, the severe criticism and pressure to which these views exposed Muller caused him to leave the United States. A year later he ended up in Leningrad directing the genetics laboratory at the Institute of Applied Botany. Eventually, Stalin's reign of terror and disagreements with Trofim Lysenko led Muller to leave for Scotland, where he and S.P. Ray-Chaudhuri studied mutation frequency and dose rate dependence. About this time, he began warning about needless exposures to radiation and their associated risks of cancer and hereditable genetic effects. By the late 1940s, the nuclear weapons testing program had begun and Muller was back in the United States, a vocal critic of the Atomic Energy Commission's views on the hazards of worldwide fallout. As a result, the AEC did not choose Muller as an official US delegate at the 1955 United Nations International Conference on the Peaceful Uses of Atomic Energy. Nonetheless, Muller attended and after virtually every presenter referenced his work, he was given an extended standing ovation!


Hermann Muller inspecting a vial of fruit flies at Indiana University. Provided by Indiana University Archives.

Thanks to the following group for allowing us to reprint this information:

The Health Physics Society
1313 Dolley Madison Blvd., Suite 402
Mclean, Virginia 22101

Tel: 703-790-1745
Fax: 703-790-2672