Chromosomes have telomeres – structures that protect them from genetic damage by dividing. From the speed with which the shortened telomeres depends on the lifespan of the organism.
“The speed of shortening of telomeres depends on the duration of life of many species. This is the best option to determine the longevity of individuals of a species than body weight or heart rate,” stated the scientists from the Spanish national research centre.
As reported by EurekAlert!, scientists conducted a comparative analysis of the value of telomeres in humans and some animals (particularly mice, goats, dolphins, gulls, deer, vultures, flamingos, elephants). The researchers found that the rapid shortening of telomeres located at the ends of chromosomes correlated with a shorter average (not maximum) lifespan.
To determine the duration of life is important, not the length of telomeres, namely, the speed at which they are reduced, said the authors of the project. According to them, some animals have telomeres of an impressive size, but they shrink incredibly quickly, and this determines a very short life of living beings. For example, such telomeres are inherent in the mice – they lose per year 7 000 base pairs. For comparison: human telomeres are shortened by 70 base pairs annually. Incidentally, this rate of reduction of telomeres in the chromosomes of the human body suggests that the average life expectancy is 79 years, the study showed.