Is cell death and replacement a factor in aging?

The central theme of the 3rd International Conference on Functional Genomics of Ageing was tissue regeneration as a remedial strategy to address age-related cellular damage and the pathology that ensues. The conference included sessions on maintaining genome integrity and the potential of stem cells to restore function to damaged tissues. In addition to several human syndromes that appear to reflect accelerated ageing, there are now a number of mouse models that prematurely display phenotypes associated with ageing. The intent of this summary presented at the end of the conference was to: (1) discuss various human syndromes and mouse models of accelerated ageing; (2) evaluate whether the phenotypes displayed might result from an elevated rate of cell death coupled with an inability to adequately maintain cell number in various tissues with increasing age; and (3) discuss whether similar events may be occurring during normal ageing, albeit much more slowly.