Genetic changes, known as bodily mutations, occur in all cells and are largely harmless, but some can start a cell on its way to cancer or impair normal function. Dr. Alex Keegan, the study’s lead author, said: “Finding a similar pattern of genetic changes in animals as diverse as a mouse and a tiger was amazing. “But the most exciting aspect of the study must be the finding that life expectancy is inversely proportional to the rate of physical mutation. “This suggests that body mutations may play a role in aging.” The team analyzed genetic errors in the stem cells from the intestines of 16 mammals and found that the longer a species lives, the slower the rate at which mutations occur. The average number of end-of-life mutations between species was about 3,200, suggesting that there is a critical mass of errors after which a body may not function properly.
“Aging is a complex process”
Although the number differed about three times between species, the variation was much smaller than the variation in body size, which ranged up to 40,000 times.
Researchers believe that the study opens the door to understanding the aging process and the inevitability and timing of death.
Dr Inigo Martincorena, the study’s lead author, said: “Aging is a complex process, the result of multiple forms of molecular damage to our cells and tissues.
“Body mutations have been thought to contribute to aging since the 1950s, but their study has remained difficult.
“With recent advances in DNA sequencing technologies, we can finally explore the roles that bodily mutations play in aging and multiple diseases.”
The research was published in the journal Nature.
