If scientists could identify longevity genes in humans, then in theory, they might also be able to develop ways to manipulate those genes to enable people to live much longer than they do today. Even more importantly, longevity assurance genes may provide us clues to how we can prevent disease and thereby live healthier.

Most longevity assurance genes already identified in lower organisms such as yeast, fruit flies and worms act to increase life span and grant resistance to a particularly destructive environmental stress. For example, scientists have identified single genes in roundworms that can extend life spans from 40-100%. These genes act by enabling worms to resist often fatal temperature extremes, excessive levels of toxic free radicals (cellular waste products) or damage due to ultraviolet light.^1,2

Some of the longevity assurance genes in lower organisms have analogous human or mammalian genes, which scientists are now studying. While these researchers have not yet found genes that predispose us to greater longevity, others have identified single human genes that seem to have a protective effect against certain age-related diseases and are associated with long life. For example, inheriting one version of a gene for a particular protein called apolipoprotein E (apoE) may decrease a person's risk of developing heart disease. Identifying and then manipulating versions of these kinds of protective genes may not produce super-longevity, but they may help us to live better, longer.