Understanding lifespan: Genes may unlock path to healthier aging, scientists say
Baku, February 3, AZERTAC
How long a person lives may be far more strongly shaped by genetics than previously believed, according to a new Israeli study challenging long-held views about aging and longevity, according to TPS-IL.
The research, led by Weizmann Institute of Science doctoral student Ben Shenhar and Prof. Uri Alon, suggests that inherited genetic factors account for roughly 50 percent of the variation in human life expectancy—more than double earlier estimates. Understanding the genetic mechanisms behind lifespan could lead to therapies targeting aging itself, not just age-related diseases.
Shenhar told The Press Service of Israel that the findings mark a significant shift in how longevity should be studied.
“Our breakthrough essentially corrected previous methodologies,” Shenhar said. “For the first time, we neutralized external causes of death in existing databases and saw that genetics plays a much larger role than previously thought in determining the lifespan of healthy people.”
For years, most studies estimated that genetics explained only about 20 to 25 percent of human lifespan, with some large-scale analyses placing the figure even lower. Environmental influences such as lifestyle, infectious disease, accidents, and socioeconomic conditions were widely believed to be the dominant factors.
According to Shenhar, those conclusions were skewed by a key limitation: earlier models did not sufficiently distinguish between deaths caused by biological aging and deaths resulting from external factors. In previous generations, high rates of mortality from infections, unsafe working conditions, and limited medical care obscured the underlying genetic contribution to lifespan.
To reexamine the question, Shenhar and his colleagues used mathematical modeling and analyzed data from three large twin registries in Sweden and Denmark, including records of twins who were raised apart. This dataset, he said, allowed the researchers to separate genetic effects from environmental influences with greater precision.
When deaths unrelated to aging were properly accounted for, the inherited component of lifespan rose sharply, reaching about 50 percent. The result, according to the researchers, aligns more closely with heritability estimates seen in other complex human traits and in animal models used to study aging.
Shenhar said the findings could have important implications for future research. If genetics plays such a substantial role in longevity, it strengthens the case for identifying specific genetic variants associated with longer life and healthier aging.
As a result, researchers can now more confidently search for specific genetic variants that influence lifespan, using them as a window into the biological mechanisms of aging.
The study opens the door to developing therapies that go beyond treating individual illnesses — such as heart disease or cancer — and instead target the fundamental processes of aging itself. For example, genes that influence dementia — responsible for about 70% of the risk by age 80 — could help scientists develop ways to prevent or slow memory loss.
“Our study lays the groundwork for future genetic research into aging,” he said. “The next step is to understand what happens beyond genetics, including how factors like nutrition, exercise, and stress interact with genetic predisposition to shape how long and how well people live.”
The findings were recently published in the peer-reviewed Science journal.
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