More common than we thought?

The number of mutations that may contribute to aging may be significantly higher than previously thought, according to new research on fruit flies. A study by scientists at the University of Linkપping in Sweden supports a new theory about the type of change behind old age. The results have been published in BMC Biology.

We live, we age and we die. Many functions of our body gradually deteriorate but as we age, and eventually an organism dies. The idea may not be very encouraging, but most of us have probably accepted that this is the destiny of all living beings – death is a part of life. However, it is not clear to those who study evolutionary biology why this is the case.

“The evolution of old age, by the way, is a paradox,” says Urban Friberg, a senior lecturer in the physics department of the Department of Chemistry. Says Friberg. And a leader in biology and studies at Linkping University.

About 70 years ago, evolutionary biologists suggested two different theories about different types of mutations that contribute to aging. Both of these mutations have a detrimental effect as the organism ages – leading to aging – when it is either beneficial or neutral early in life. Researchers, however, have not been able to determine which of the two types of mutations contributes the most to aging, despite experimental studies.

A new theory was suggested a few years ago to suggest that aging is caused by mutations with harmful effects early in life and whose negative effects increase with age. Those who support this hypothesis believe that the onset of many of the changes that occur have a negative effect compared to the normal variability of genes.

The now-published study describes experiments to test the theory of change which has a detrimental effect on lifelong life and contributes to aging. The authors have used one of the most well-studied animals in the world, such as the fruit fly or Drosophila melanogaster. He tested 20 different mutations in the genetic material of the flies. For each individual change, they studied the group of flies with the change and the control group without it. Each change has a specific, visible effect, making it easier to observe, such as the slightly different look of the wings or the different shape of the eyes.

As the organism ages, the probability of a person dying increases, and his fertility decreases. Researchers determined the fertility of fruit flies and used them as a measure of aging. They count the number of eggs laid by each female at the beginning of life after two weeks, and finally after two more weeks (which is the old age lined up for the fruit fly!). The researchers wanted to see if the difference between the flies with the change and the control group changed with their age. The results support the theory they were testing. Most of the changes had a negative effect on the fertility of the flying fruit early in life, and most of them also cause reproductive aging to occur more quickly.

“The results suggest that even harmful changes early in life may contribute to aging. Thus, the changes that bring about change are significantly more common than we previously believed,” says Martin Inati Brandahl, a doctoral student in the Department of Physics, Chemistry and Biology. .And author of Knowledge and Studies.