Genetic control of adult lifespan in Drosophila melanogaster

Two temperature-sensitive X-linked adult lethal mutations were induced by ethyl methane sulfonate in Drosophila melanogaster. These mutations exhibited both a temperature-sensitive and effective lethal phase in adult flies. The existence of this new class of gene mutations provides experimental support for the hypothesis of H.J. Müller (1963, p. 235) that "development is a continuous process of which senility forms the last state." Furthermore, their existence demonstrates that the role of genes in controlling adult lifespan may be dissected by those methods that have been used to successfully probe the genetic control of preadult development.