A receptor from the past
Neanderthals vanished roughly 42,000 years ago, but a piece of their biology still works in some people today. A new study led by scientists from the Max Planck Institute for Evolutionary Anthropology shows that a gene variant inherited from Neanderthals still shapes muscle and jaw structure in living humans.
The researchers examined the growth hormone receptor, a protein that helps control how the body responds to growth hormone released by the pituitary gland. Comparing modern human DNA with high-quality Neanderthal genomes, they found that Neanderthals carried a distinctive version of the receptor marked by two amino acid changes not found in Africans today.
Lab and population evidence align
To test what the two changes do, the team engineered laboratory-grown mouse cells to produce either the Neanderthal version of the receptor or the version most common in people today. When exposed to growth hormone, cells with the Neanderthal receptor grew about 40% more over several days. Most of that stronger response traced back to one of the two Neanderthal-specific changes.
The human evidence came from five biobanks holding genetic and health data from more than 1.1 million adults. Across those datasets, carrying the Neanderthal-derived variant was linked to roughly 270 to 285 grams of extra lean mass and about 0.3 centimeters of extra height. These are averages across large groups, not changes that would be noticeable in any one person.
'It is rare to see laboratory and population evidence fit together so clearly,' said Philipp Kanis, first author of the study and a postdoctoral researcher at the Max Planck Institute.
What it means today
The variant is common in people with European and Asian ancestry and is rare or absent in sub-Saharan Africa, which matches the pattern of Neanderthal interbreeding. Dr. Hugo Zeberg, also from the Max Planck Institute, said it is fascinating that one genetic change inherited from Neanderthals can still affect the human body today.
The study appears in the journal Genetics. Researchers say the findings help explain the robust build of Neanderthals and show how ancient interbreeding continues to influence human biology.