The quest for an anti ageing pill is boosted today with the discovery of 15 genes linked with a long life. The find suggests that scientists may be able to target those genes to help slow down the aging process and treat age-related conditions.

Scientists at the University of Washington and other institutions report in the journal Genome Research that they have identified 25 genes that influence lifespan in two organisms, yeast and the roundworm C. elegans, and at least 15 of those genes have similar versions in humans,

The two organisms used in this study are commonly used in ageing research. Finding genes that are the same in he two organisms is significant, researchers say, because the two species are so far apart on the evolutionary scale - even farther apart than the tiny worms and humans.

That, combined with the presence of similar human genes, is an indication that these genes could regulate human longevity as well.

"Now that we know what many of these genes actually are, we have potential targets to go after in humans," says Dr Brian Kennedy, one of the senior authors.

"We hope that in the future we could affect those targets and improve not just lifespan, but also the 'health span' or the period of a person's life when they can be healthy and not suffer from age-related illnesses."

Several of the genes that the scientists identified as being involved in ageing are also connected to a the way the body responds to food. Previous studies have found that drastically restricting the caloric intake, an approach known as dietary restriction, can prolong lifespan and reduce the incidence of age-related diseases.

Drugs based on this understanding are being tested clinically in people for anti-cancer properties, and this work suggests they may also be useful against a variety of age-associated diseases.

"What we'd like to eventually do is be able to mimic the effects of dietary restriction with a drug," explains Prof Matt Kaeberlein, another author of the study with Prof Jim Thomas and Dr Erica Smith.

"Most people don't want to cut their diet that drastically, just so they may live a little longer," says Prof Kaeberlein. "But someday in the future, we may be able to accomplish the same thing with a pill."