6. Somatic DNA alterations and aging

Aging can be defined as a series of time-related processes occurring in the adult individual that ultimately bring life to a close. To some extent, these processes can be understood as the coordinated action of the products of multiple genes. However, aging also has a major stochastic component. Random DNA alterations, induced by both environmental and endogenous mutagens and carcinogens fall into this category and have been considered as a most likely primary cause of aging. While the age-related accumulation of DNA damage and mutations has now been amply demonstrated in various organisms, the functional relationship of this accumulation with the aging phenotype remains unclear.