DNA-damage & DNA-repair in ageing brain.

The validity of DNA damage and repair hypothesis of ageing has been examined with special reference to the brain. As far as the accumulation of DNA damage is concerned, the data appear to overwhelmingly support the hypothesis. However, the results of attempts to demonstrate a decline in DNA repair capacity as a function of age are conflicting. However, more recent observations are in support of age-dependent deterioration in DNA-repair capacity. Possible reasons for this discrepancy and the usefulness of conducting DNA damage and repair studies in a model system of isolated neuronal cells, are discussed. It is suggested that assessment of repair capacity of brain with respect to a specific damage in a designated gene might yield more definitive answers regarding the role of DNA repair potential in the ageing process and as a longevity assurance system.