Ancient Neanderthal gene variant boosts muscle growth in a subset of people
A Cell study shows a Neanderthal variant of the growth hormone receptor entered the modern human gene pool about 47,000 years ago, boosting how cells respond to growth hormone. People with one copy may gain around 270 grams of extra muscle per copy, while two copies could add over 0.5 kg (about 1.2 pounds). The variant now appears in roughly 10% of people, with higher frequencies in Southern and Southeast Asian populations and little to none in those of African ancestry. It may also subtly affect jaw shape and tooth roots, and effects seem to emerge during puberty when growth hormone rises, indicating it's not the sole reason Neanderthals were robust but a piece of the puzzle.
