Telomeres, which are caplike DNA structures at the tips of chromosomes, have long been suspected of playing a pivotal role in aging. A new study of worms adds to the case. Worms with longer telomeres live longer than do counterparts with shorter telomeres, Korean researchers report in the June Nature Medicine.
With every division, a cell's chromosomes get shorter by shedding portions of their telomeres (SN: 11/25/95, p. 362). Researchers have theorized that when telomeres get too short, cells enter a nondividing state called senescence. The effects of aging, in part, may result from the buildup of senescent cells (SN: 1/17/98, p. 37).