In that telomeres are the endcaps on chromosomes, and telomeric shortening is thought to govern the number of times a cell can divide, telomeric replication is governed by an enzyme, telomerase. Gil Atzmon, from Albert Einstein College of Medicine (New York, USA), and colleagues studied Ashkenazi Jews, a population group that generally lives well into their 90s and beyond, in a generally healthy condition. The researchers found that participants who have lived to a very old age have inherited mutant genes that make their telomerase-making system extra active and able to maintain telomere length more effectively. For the most part, these people were spared age-related diseases such as cardiovascular disease and diabetes, which cause most deaths among elderly people. The team observes that: “As we suspected, humans of exceptional longevity are better able to maintain the length of their telomeres. [T]hey owe their longevity, at least in part, to advantageous variants of genes involved in telomere maintenance.”
Living to 100 Linked to Variant of Telomere Enzyme
Gil Atzmon, Miook Cho, Richard M. Cawthon, Temuri Budagov, Micol Katz, Xiaoman Yang, Glenn Siegel, Aviv Bergman, Derek M. Huffman, Clyde B. Schechter, Woodring E. Wright, Jerry W. Shay, Nir Barzilai, Diddahally R. Govindaraju, Yousin Suh. “Genetic variation in human telomerase is associated with telomere length in Ashkenazi centenarians.” PNAS, online before print November 13, 2009, doi:10.1073/pnas.0906191106.
