There are number of areas where scientists are exploring the link between telomeres, telomerase and aging.

For example, one group of researchers recently looked at the cells of people with progeria, the disease that ages young children so rapidly that they die with many of the symptoms of old age in their teens. Their cells have exceptionally short telomeres, suggesting that rapid shortening of telomeres contributes to the pathology of their disease, and providing more support for the hypothesis that such shortening explains much of cellular aging.¹

Cancer and some other cells can overcome the limits of telomere shortening and become immortal. They do this by making use of the enzyme, telomerase, which acts to restore some of the shortened segments of telomeres. Using the one-cell organism Tetrahymena, Professors Greider and Blackburn² found that adding telomerase recreated enough of the Tetrahymena's shortened telomeres to allow unlimited reproduction, creating what amounted to an immortal strain of this organism.

Researchers have also developed a type of laboratory mouse whose native telomerase is defective. Selective breeding of these mice produced successive generations with signs of premature aging and shortened life spans,³ providing further evidence of the role of telomeres and telomerase in aging.

Telomerase has been found in as many as 90% of human cancer cells-but it is absent in adjacent healthy cells.⁴ This observation has led to speculation that medications that inhibit telomerase could be effective anti-cancer drugs.⁵