Credit: Paul Jerem
Clue to Life Span Found at a Young Age
Now, scientists haveِ foundِ that theِ length ofِ these caps, called telomeres, measured early inِ life canِ predict life span.
Using 99 zebra finches, a small bird alsoِ popular asِ a pet, a team ofِ researchers inِ the United Kingdom measured theِ lengths ofِ the telomeres foundِ in theِ birds’ red blood cells overِ the courseِ of theirِ lives.
In addition, theِ birds withِ theِ longest telomeres early inِ life, andِ throughout theِ study, wereِ theِ onesِ mostِ likelyِ to live intoِ old age, upِ toِ 8.7 years oldِ — a ripe oldِ age forِ a finch, saidِ study researcher Britt Heidinger, a postdoctoral researcher atِ the University ofِ Glasgow.
The basics of aging and telomeres
Chromosomes areِ threadlike strands ofِ protein andِ DNA (deoxyribonucleic acid), whichِ containِ the instructions toِ makeِ a living thing.
Each ofِ our cells containsِ chromosomes, capped byِ telomeres, andِ when ourِ cells divide — a necessaryِ part ofِ growth andِ the maintenance ofِ our bodies — theseِ chromosomes mustِ beِ duplicated.
Eventually, withِ age, theِ telomeres shorten toِ a point whereِ theِ cell canِ no longer divide, andِ most normal cells cease toِ function.
Cause of death
In order toِ complete theِ study, theِ birds wereِ allowed toِ live outِ their natural lives, withِ blood samples takenِ when theyِ were 25 days old, thenِ 1 year old, andِ periodically afterward.
The researchers didِ not track theِ birds’ eventual causeِ of death, butِ they knowِ these didِ not include accidents, predators, starvation orِ infection.
Many otherِ factors — damage elsewhereِ in theِ DNA, accumulating damage toِ biologically important molecules, reduced capacity toِ replace lost cells, andِ so onِ — areِ alsoِ implicated inِ aging.