Hermann Muller. Portrait of Hermann Joseph Muller (1890-1967), American geneticist. Muller researched gene mutations and noted that they were rare, (usually) detrimental and recessive. In 1926 he discovered that mutations in the fruit fly Drosophila were easily achieved by using X-rays. Muller was the first to highlight the effect on human genes of X-rays and other radiation. Muller argued that the gene was the origin of life and was responsible for evolution. Concerned about mutations surviving in human genes due to medical technology, Muller argued for a eugenics programme. In 1946, Muller was awarded the Nobel prize for medicine.