ABSTRACT
Aging is inevitable and has always fascinated mankind. Still, its basic course and the genetic keys that necessarily must be involved in the regulation of the complicated processes involved are largely unknown. An aged individual is easy to recognize compared to a child or young adult. Wrinkling skin, graying and thinning hair, hardening eye lenses, and changing posture are apparent and wellknown manifestations of aging. Morphological studies of aged individuals also reveal some structural disorganization of most organs and tissues, a decreased proportion of functional elements with an increased amount of stroma, and im pairment of vascularization and innervation. These age changes chiefly represent alterations of the extracellular matrices due to glucosylation, oxidation, and cross linkings of various proteins and, although they may be much disturbing to the individual, they certainly do not threaten life.
