From Scientific American:
Can we tweak certain genes to stave off the aging process–or, conversely, to speed it up? New research indicates that it may one day be possible. Scientists have discovered genetic switches in roundworms (Caenorhabditis elegans)—whose genetic makeup is remarkably similar to that of humans—that apparently cause the spineless critters to grow old when flicked on but, when off, may extend their lives. “This is a new and potentially powerful circuit that has just been discovered,” says Brown University biologist Marc Tatar, who was not involved in the study. “The take-home message is that aging can be slowed and managed by manipulating signaling circuits within cells.”
The new finding challenges the prevailing theory of aging, which is that our bodies wear out, or “rust,” in much the same way as cars and other machines due to damage inflicted on our cellular DNA (genetic material) by factors such as smoking, disease, the sun’s ultraviolet rays and chemically reactive molecules called free radicals, which are produced when our cells make energy. It suggests instead that a combination of factors is at play—that in addition to rusting, there are also certain genes that may carry instructions to start the aging process.