Family of genes extends lifespan

Four cousins of a known longevity gene have been found to extend lifespan as well, suggesting that the entire family influences longevity and providing targets for new drugs that fight aging.

The gene, SIR2, is thought to play a role in the life extending benefits of a low-calorie diet.

Researchers at Harvard Medical School and the University of California, Davis have now discovered that four cousins of SIR2 also extend lifespan.

"We think these new Sir2 genes are as important as any longevity genes discovered so far," says molecular biologist David Sinclair, coauthor of the new study. "There is a growing realization from the aging field that we might finally understand how to control certain aspects of the aging process and one day have drugs that can fight some of the disabilities the process causes."

Sinclair's research group previously reported a genetic link between environmental stresses and longer life.

They found that such stresses as low salt, heat or extreme calorie restriction triggered a longevity
regulator called PNC1 that stimulated SIR2 activity.

The new study, reported in the journal Science and led by Harvard graduate student Dudley Lamming, shows that PNC1 regulates the entire SIR2 family of genes.

The find suggests that a human PNC1 gene might protect against diseases of aging.