Boston: Scientists at the Paul F Glenn Laboratories for Ageing Research at Harvard Medical School have discovered a whole family of genes that appear to control longevity.

In experiments on mice it has been discovered that they can been made to live longer on a low calorie diet. A gene called SIR2 is thought to be involved in this process, which also protects mammals against cancer and other age-related illnesses.

The scienits at Harvard have found four cousins of SIR2 that also seem to play a role in extending lifespan.

The research suggests potential targets for developing drugs to lengthen life and prevent or treat diseases associated with ageing.

Dr David Sinclair, director of the Paul F Glenn Laboratories for Ageing Research at Harvard Medical School in Boston, US, who co-led the study, said: “We think these new SIR2 genes are as important as any longevity genes discovered so far.

“There is a growing realisation from the ageing field that we might finally understand how to control certain aspects of the ageing process and one day have drugs that can fight some of the disabilities the process causes.” The new findings appear today in the online edition of the journal Science.

Dr Sinclair’s team previously reported the first genetic link between environmental stresses and lifespan.

Experiments with yeast showed that low salt, heat or extreme calorie restriction triggered a “master longevity regulator” called PNC1 which in turn stimulated SIR2 activity.

The new research demonstrates that PNC1 regulates a whole SIR2 family of genes. It suggests a human PNC1 gene might protect against diseases of ageing such as cancer, heart disease and diabetes.