It has been shown that most of Drosophila melanogaster mutant lines obtained as a result of X-rays irradiation (XI) as well as of the combined action of XI and some chemical agents are characterized by decreased indexes of average (7-40 %) and maximal (1-35 %) life span. Insertion-excision processes at the instable genes white and cut are among the reasons of decreased vitality and shortened life span in induced mutants. Collection of neurodegenerative mutants has been obtained under the influence of ENU. Fast dying of flies and decreased vitality correlated with time point of neurodegenerations in brain structure.