MDM2 encodes the murine double minute 2 protein, an E3 ubiquitin ligase and a principal regulator of the p53 tumor suppressor, to which it is linked in a negative feedback loop. P53 plays an essential role in tumor development and is the most commonly mutated gene in somatic cells in human cancers. Additionally, it has been associated with premature aging in mice. However, the mechanism by which disturbed interaction between MDM2 and p53 may impact on human aging has not yet been elucidated. A team of international researchers led by Christian Kubisch, director of the Institute of Human Genetics at UKE Hamburg, has now discovered a causative homozygous MDM2 mutation in a patient affected by a segmental progeroid syndrome manifesting several symptoms of premature aging. By extensive functional analyses using patient cells and an animal model, the scientists were able to show that the identified mutation affects MDM2 activity and gives rise to increased p53 levels and stability. The results of their study, published in the Journal of Clinical Investigation, suggest that disruption of the MDM2/p53 axis promotes premature aging in humans.