An unexpected way to determine life expectancy has been found

An international team of researchers has developed a new method for assessing biological age based on gene activity. According to the authors, the method allows for more precise tracking of aging processes and is linked to the risk of death and the development of chronic diseases. The results of the study have been published in the journal Nature.

Unlike chronological age, which indicates the number of years lived, biological age reflects the state of the body and the rate at which it is aging. To assess it, scientists often use so-called epigenetic clocks, which analyze chemical marks on DNA. However, such methods do not always work equally well for different organs and animal species.

The new approach is based on the analysis of RNA — molecules that carry information from genes to the cellular machinery responsible for protein synthesis. By studying which genes are active at a given moment, the researchers created what are known as transcriptomic aging clocks.

The scientists analyzed more than 11,000 tissue samples from four mammalian species — humans, macaques, rats, and mice. This made it possible to compare aging processes across different organs and even across different animal species.

It turned out that certain groups of genes quite accurately reflect the rate of aging in an organism. For instance, higher activity of genes associated with cell division, tissue repair, and wound healing corresponded to slower biological aging. Conversely, increased activity of genes involved in inflammation and cell death indicated accelerated aging.

Based on these patterns, the researchers created an algorithm capable of assessing biological age and the risk of death. When analyzing human blood samples, the new system predicted life expectancy no worse than the best modern epigenetic clocks. In addition, the method successfully identified signs of accelerated aging in animals with chronic diseases and in patients with various pathologies.

The authors believe that the new tool could prove useful for evaluating the effectiveness of potential rejuvenating drugs and various interventions aimed at slowing aging. Instead of conducting studies lasting many years, scientists will be able to more quickly determine whether a given therapy affects biological age.