title: Blood cell telomere lengths and shortening rates of chimpanzee and human females.
abstract: OBJECTIVE
  Slower rates of aging distinguish humans from our nearest living cousins. Chimpanzees rarely survive their forties while large fractions of women are postmenopausal even in high-mortality hunter-gatherer populations. Cellular and molecular mechanisms for these somatic aging differences remain to be identified, though telomeres might play a role. To find out, we compared telomere lengths across age-matched samples of female chimpanzees and women.
  
  
  METHODS
  We used a monochrome multiplex quantitative polymerase chain reaction to assay canonical telomere repeats in blood cells from captive female chimpanzees (65 individuals; age: 6.2-56.7 years) and compared them to the same measure in human females (43 individuals; age: 7.4-57.3 years).
  
  
  RESULTS
  Our samples showed little difference in attrition rates between the species (~0.022 T/S per year for chimpanzees and ~0.012 T/S per year for humans with overlapping 95% confidence intervals), but telomeres were twice as long in chimpanzees as in humans (T/S ratios = 2.70 and 1.26, respectively).
  
  
  CONCLUSIONS
  Based on the longevity differences, we initially hypothesized that telomere shortening rates would be faster in chimpanzees than in humans. Instead, it is shorter telomere length that appears to be the derived state in humans. This comparison indicates that better characterization of physiological aging in our closest living relatives will be indispensable for understanding the evolution of distinctive human longevity.
authors.affiliation: Department of Anthropology, University of Utah, Salt Lake City, Utah, 84112.
authors.forename: Justin
authors.initials: J
authors.lastname: Tackney
authors.forename: Richard M
authors.initials: RM
authors.lastname: Cawthon
authors.forename: James E
authors.initials: JE
authors.lastname: Coxworth
authors.forename: Kristen
authors.initials: K
authors.lastname: Hawkes
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000166:cytology*; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D002679:Pan troglodytes / Q000235:genetics*; D016615:Telomere / Q000235:genetics*; D059506:Telomere Shortening; D055815:Young Adult