"Longevity genes" don't work for everyone

There have long been good reasons to suspect that a person's DNA affects how they age and how long they live. But it is still unclear whether there is a direct genetic regulation of life expectancy.

In a new study conducted on 3,200 genetically diverse mice, a group from the University of Tennessee at Memphis, the University of Birmingham and the Swiss Federal Institute of Technology in Lausanne identified several fragments of the genome that affect life expectancy. Some of these genes differed in male and female mice, and some affected life expectancy only in mice that had reached a certain age. Thus, one locus of chromosome 12 affected the life expectancy of all mice, and the life expectancy of females was also affected by the locus of chromosome 3 (mice have 20 pairs of chromosomes).

In males, the analysis was more complicated. Many male mice die young, probably due to social interactions between males. After the authors excluded these deaths of young mice from their analysis, they found five chromosomal regions that influenced the life expectancy of males who lived to an older age.

The loci identified by the researchers are very large (more than 100 genes in each), so it is not yet clear which genes regulate longevity and what processes they affect. The question remains: do they directly determine life expectancy? After all, genes can also prolong life by protecting against certain diseases, such as cancer. The researchers also examined the mechanisms by which longevity genes can act, and found a reliable link between life expectancy and growth rate. It is known that mice born in a small litter die earlier because they grow faster in the womb. The team found that one chromosomal region that determines life expectancy may be associated with growth rates.

The team then used data from the British Biobank to show that people who grow faster in childhood also have a shorter life expectancy, probably because they have a higher body mass index in adulthood. Taken together, the results support the idea that early growth rates affect life expectancy.

Discovering the true longevity genes will help researchers develop measures that will allow people to stay healthy longer.

Article M.Bou Sleiman et al. Sex- and age-dependent genetics of longevity in a heterogenic mouse population is published in the journal Science.

Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru .