Hermann Joseph Muller was an American geneticist who was awarded the 1946 Nobel Prize in Physiology or Medicine "for the discovery of the production of mutations by means of X-ray irradiation". Muller warned of long-term dangers of radioactive fallout from nuclear war and nuclear testing, which resulted in greater public scrutiny of these practices. The Nobel Prize in Physiology or Medicine 1946, announced October 31, 1946. Hermann J. Muller, “for the discovery of the production of mutations by means of X-ray irradiation”. Hermann J. Muller: born 1890, New York, NY, USA. Wiki link Data: the Nobel Foundation (CC0).