The candles on your birthday cake tell you how many years you’ve lived through, but they might not be a reflection of your biological age.
Little bits of DNA called telomeres protect the ends of chromosomes. Over time, through repeated rounds of cell division, telomeres get shorter and shorter. Thus, telomere length is a marker of biological aging. Research recently published in the journal Nature Genetics that found a common DNA variation associated with telomere length suggests that some people are genetically programmed to age at a faster rate.
Researchers from the University of Leicester and King’s College London analyzed the DNA of more than 12,000 Europeans. They found that each copy of the less common G version of the SNP was associated with about a 75 base pair reduction in average telomere length. This is equivalent to about 3.6 years of biological aging as measured by telomere length loss.
This finding could have important implications because biological aging isn’t just a matter of wrinkles and aching joints. Shorter telomeres have been linked with age-associated conditions such as heart disease and certain types of cancer. But that’s not to say that people with variants that predict shorter telomeres should give up on doing all they can to keep young.
“Genetically susceptible people may age even faster when exposed to proven ‘bad’ environments for telomeres like smoking, obesity or lack of exercise–and end up several years biologically older and succumbing to more age-related disease,” said one of the study’s senior authors, Tim Spector of King’s College London, in a press release.
- A previous Blog post about telomeres can be found here.
- You may have heard about telomeres in the news recently: The Nobel Prize in Physiology or Medicine 2009 was awarded jointly to Elizabeth Blackburn, Carol Greider and Jack Szostak “for the discovery of how chromosomes are protected by telomeres and the enzyme telomerase.”