Overview
- A Weizmann Institute–led team reported in Science that reanalyses of Danish and Swedish twin registries and U.S. cohorts, including SATSA twins raised apart, support a higher genetic contribution to lifespan.
- The work combined classical mortality models such as Gompertz–Makeham with a mechanistic "saturable elimination" aging model to run counterfactual simulations that removed extrinsic deaths like accidents and infections.
- Across datasets, the estimated heritability of intrinsic longevity clustered around 50–55% when defined under zero extrinsic mortality and age cutoffs that exclude early-life deaths.
- This revised estimate places human longevity in line with the heritability of complex traits such as height and blood pressure and with lifespan patterns observed across species.
- Independent experts caution that the result hinges on modeling choices and does not identify specific genetic variants, and the authors note that environment and stochastic biology still account for roughly half of lifespan variation.