From Nature:
Protective caps known as telomeres that help to preserve the integrity of chromosomes can also predict lifespan in young zebra finches (Taeniopygia guttata), researchers have found.
Telomeres are stretches of repetitive DNA sequence that are found at the ends of chromosomes, where they help to maintain cell viability by preventing the fraying of DNA and the fusion of one chromosome to another. The relationship between normal ageing and telomere decline has long been suspected — and even asserted by some companies that measure customers’ telomere length — but the link remains unproven in humans (see 'Spit test offers guide to health').Most studies of longevity and telomere length have relied on only one or two measurements from an individual during their lifespan. But population ecologist Pat Monaghan of the University of Glasgow, UK, and her colleagues found that measuring telomere length periodically over the course of a zebra finch’s life revealed a tight association between length and lifespan — particularly when those measurements were taken when the birds were only 25 days old. The results are reported online this week in Proceedings of the National Academy of Sciences.
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