The molecular mechanisms of aging are most fully understood for the budding
yeast Saccharomyces cerevisiae. Recent advances in our understanding of ag
ing in this organism have enabled researchers to answer some fundamental qu
estions about the aging process. Is aging due to a multitude of 'mechanisms
' or can there be a key few? Can we design single-gene mutations that will
prolong life? Can we prolong life whilst maintaining health and fecundity?
The various contributing factors to yeast longevity, uncovered thus far, fa
ll into three classes: DNA metabolism, heterochromatin, and metabolic activ
ity. However, these separate classes may actually represent different aspec
ts of the same aging mechanism based on genome stability. This review exami
nes the recent advances in our understanding of yeast aging and discusses t
heir relevance, if any, to the human condition.