Telomere shortening rate predicts species life span

Abstract

Telomere shortening to a critical length can trigger aging and shorter life spans in mice and humans by a mechanism that involves induction of a persistent DNA damage response at chromosome ends and loss of cellular viability. However, whether telomere length is a universal determinant of species longevity is not known. To determine whether telomere shortening can be a single parameter to predict species longevities, here we measured in parallel the telomere length of a wide variety of species (birds and mammals) with very different life spans and body sizes, including mouse (Mus musculus), goat (Capra hircus), Audouin's gull (Larus audouinii), reindeer (Rangifer tarandus), griffon vulture (Gyps fulvus), bottlenose dolphin (Tursiops truncatus), American flamingo (Phoenicopterus ruber), and Sumatran elephant (Elephas maximus sumatranus). We found that the telomere shortening rate, but not the initial telomere length alone, is a powerful predictor of species life span. These results support the notion that critical telomere shortening and the consequent onset of telomeric DNA damage and cellular senescence are a general determinant of species life span.

Keywords: life span; species; telomere.

Fig. 1.

Telomere measurements for various species. The telomeres were measured by HT Q-FISH in individuals of different ages for (A) mice (Mus musculus), (B) bottlenose dolphins (Tursiops truncatus), (C) goats (Capra hircus), (D) reindeer (Rangifer tarandus), (E) American flamingos (Phoenicopterus ruber), (F) griffon vultures (Gyps fulvus), (G) Audouin’s seagull (Larus audouinii), and (H) Sumatran elephants (Elephas maximus sumatranus). Each point represents the values for a different individual. The correlation coefficient (R²), slope (rate of telomere shortening in kilobases per year), and y intercept (initial telomere length) are presented on the graphs.

Fig. 2.

Species life span predictions with telomere parameters I. (A) Maximum life span vs. estimated initial telomere length fit with a linear regression line. (B) Maximum life span vs. estimated initial telomere length fit with a power law regression line. (C) Average life span vs. estimated initial telomere length fit with a linear regression line. (D) Average life span vs. estimated initial telomere length fit with a power law regression line. (E) Maximum life span vs. rate of telomere shortening. (F) The predicted life span vs. the maximum life span. The predicted life span is calculated by using the telomere shortening rate in the power law regression equation from E. (G) Average life span vs. rate of telomere shortening. (H) The predicted life span vs. the average life span. The predicted life span is calculated by using the telomere shortening rate in the power law regression equation from G.

Fig. 3.

Species life span predictions with telomere parameters II. (A) The estimated life span if telomeres shortened to 50% of the original length vs. the maximum life span. (B) The estimated life span if telomeres shortened to 50% of the original length vs. the average life span. (C) The estimated life span if telomeres shortened to 75% of the original length vs. the maximum life span. (D) The estimated life span if telomeres shortened to 75% of the original length vs. the average life span. The estimated life span is calculated using the following equation: (“Telomere length original” − “Telomere length original” × “percent of original length”)/“Telomere shortening rate.” (E) Graphical illustration which shows the main finding from this paper, which is that faster telomere shortening rates result in shorter species life spans.