From Phys.Org:
The first study to compare the accumulation of mutations across many animal species has shed new light on decades-old questions about the role of these genetic changes in aging and cancer. Researchers from the Wellcome Sanger Institute found that despite huge variation in lifespan and size, different animal species end their natural life with similar numbers of genetic changes. The study, published today in Nature, analyzed genomes from 16 species of mammal, from mice to giraffes. The authors confirmed that the longer the lifespan of a species, the slower the rate at which mutations occur, lending support to the long-standing theory that somatic mutations play a role in aging.
Genetic changes, known as somatic mutations, occur in all cells throughout the life of an organism. This is a natural process, with cells acquiring around 20 to 50 mutations per year in humans. Most of these mutations will be harmless, but some of them can start a cell on the path to cancer or impair the normal functioning of the cell. Since the 1950s, some scientists have speculated that these mutations may play a role in aging. But the difficulty of observing somatic mutations has made it challenging to study this possibility. In the last few years, technological advances have finally allowed genetic changes to be observed in normal tissues, raising hopes of answering this question.
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