People are twice as likely to inherit their lifespan than was previously thought, according to a team of researchers led by scientists at the Weizmann Institute in Israel.
The “genetic contribution” to how long a person lives is around half, the team found, following a trawl of health databases in Denmark and Sweden.
Published in the journal Science, the results could “have far-reaching implications for ageing research and public health”, according to the Weizmann Institute, whose scientists teamed up with the Karolinska Institute in Sweden and Leiden University in the Netherlands to conduct the research.
For decades, many scientists believed the input of genes and ancestry to longevity to be anything from around 10% to perhaps 25% – underestimations arising from limited historic health and death data.
“For many years, human lifespan was thought to be shaped almost entirely by non-genetic factors, which led to considerable scepticism about the role of genetics in ageing and about the feasibility of identifying genetic determinants of longevity,” said study lead author and Weizmann Institute PhD student Ben Shenhar.
Death due to war, infectious diseases, the effects of physical or unsafe work, accidents, poor diet, lack of medical care and other such “extrinsic” causes were not always easy to pick out in records.
“Environmental forces, such as disease or living conditions, exert a powerful influence on how long someone lives and often obscure or confound potential genetic effects,” said the journal’s publisher, the American Association for the Advancement of Science (AAAS).
Hereditary causes of death – for those who do not get killed first by extrinsic causes – mean “processes originating within the body, including genetic mutations, age-related diseases and the decline of physiological function with age”, the researchers said.
“If heritability is high, as we have shown, this creates an incentive to search for gene variants that extend lifespan, in order to understand the biology of ageing, and potentially, to address it therapeutically,” said Shenar.
Other recent research has pointed to a potential role for taurine, an amino acid, in slowing the ageing process.
Still other scientists have pointed to the 200-year lifespan of the bowhead whale – a longevity that has been put down to the Arctic giant having a protein in its cells that protects from carcinogenic mutations. – dpa
