Genes Hold a Stronger Grip on Lifespan Than Previously Thought
A large twin-based analysis from the Weizmann Institute estimates that about 55% of the variation in human lifespan is genetic—far higher than prior 6–25% figures—after separating intrinsic aging from extrinsic death causes and studying twins and siblings raised apart. The finding, published in Science (2026), suggests genetics has a major role in aging and will spur ongoing searches for longevity genes using modern datasets.