June 01, 2021
We can learn a lot from our elders, not just from their experience, but also from their genes, say Italian scientists who, for the first time, have decoded the DNA of people older than 100 years to figure out how they avoided age-related diseases.
"The 105 threshold is really tough to jump and those who surpass it are really super athletes in terms of aging," according to Paolo Garagnani, PhD, associate professor of general pathology at the University of Bologna, Italy.
These "super centenarians" are remarkable because they also tend to avoid the long periods of illness that so often overshadow the last few years of an older person's life, he says.
To find out what separates the oldest of the old from the average person, Garagnani and his team scoured Italy for people who had reached 105 years and sequenced their genomes to determine how they had been able to live so long.
Italy is ideal for research like this because its population has one of the longest life expectancies in the world and the Catholic Church in the region keeps precise records of baptisms, which assists researchers in verifying people's ages.
The scientists took blood samples from 81 people and conducted whole-genome sequencing to look for differences between the centenarians and younger people. And they found that people who live past 100 tend to have a unique genetic background that makes their bodies very efficient at repairing DNA.
The scientists also identified five common genetic changes between the COA1 and STK17A genes. These genes are involved in areas important to the health of human cells and the development of cancer, heart attack, and stroke, which are diseases that centenarians seem to be at a lower risk for, Garagnani says.
Most of the people the scientists met with were living independently past the age of 100 and weren't held back by illness. Often people who live this long, he explains, tend to die suddenly. "When enough is enough for them, they go in a couple of days or a week."