The biological basis of ageing: a brief guide

Improved understanding of genetics and the protective mechanisms that have evolved at the cellular level now makes it possible to present a unified hypothesis of the biology of ageing. Previously, two opposing theories of ageing - "genetic-programming" theory and "wear-and-tear" theory - led to apparently divergent research thrusts. The recognition that both theories are aspects of the same phenomenon different levels of cell function - allows a deeper understanding of the contribution that each school has made to present notions of the biology of ageing.