Age Correlated Changes in the Primary Biological Information Carrier Deoxyribonucleic Acid (DNA)

In higher organisms, the information for the respective organism as a whole is stored in each cell nucleus in the form of DNA molecules. This includes the synthesis programmes of the control molecules for both the reactions for life processes and reproduction. However, since DNA molecules are a very vulnerable type of molecule, the evolution of today's living world was only possible through the development of effective DNA repair systems. It is in the nature of things that, given the huge number of damages affecting DNA programmes and the acts of repairing them, a considerable number of errors occur. This in turn means that DNA damage can accumulate with increasing lifespan. Methods have now been developed, also in Mainz, that can detect DNA changes with high sensitivity. The largest DNA‑damage statistics compiled to date on humans have shown that, in striated muscle, DNA strand breaks increase with age and are markedly more frequent in smokers. Further experiments are underway to document the varying degrees of damage to different organs in the same individual and to investigate the temporal sequence of events, including repair capabilities. Underlying these studies is the question of whether, and to what extent, DNA changes play a role in the ageing process.