In another small step toward understanding the mystery of aging, University of Illinois, Chicago researchers say they have discovered a possible genetic link common to age-related diseases. Cancer, atherosclerosis, arthritis [1] and Alzheimer's disease may have a single [2] common gene, the researchers said in the new issue of Proceedings of the National Academy of Science.

Hopeful researchers said the discovery may ultimately make it possible to prevent or combat all these diseases with drugs targeting the common genetic link.

The focus of the research is a single [2] gene known as p21. It stops cells from growing when they're damaged by toxins or radiation to give them time to repair, researchers said. The p21 gene also stops cells from dividing.

Using DNA methods, the researchers activated the p21 gene in human cells grown in a lab. Using information on the sequence of the human genome, the researchers studied the effects of p21 on thousands of other genes.

The researchers found that p21 selectively inhibited more than 40 genes known to be involved in DNA replication and cell division, thus immediately arresting cell growth.