[Nuclear genetic material as an initial substrate for animal aging]

General properties of aging in animals are considered on the basis of the literature evidence and the results obtained by the authors of this paper. The existence of a specific aging mechanism is inferred. The operation of this mechanism is controlled not only by genes but also by particular noncoding genomic sequences with variable structure. The beginning of senescence in animals is determined by DNA lesions located in neural cells and probably in a minor genomic fraction. The authors refute the narrow concept of aging as a mechanism increasing the probability of death. Mortality as a continuous process occurring with the probability of 100 percent is an integral attribute of living organisms on the Earth.