By Daily Mail (U.S.) | Created at 2026-08-05 18:03:40 | Updated at 2026-08-05 20:53:42
5 hours ago
If you're lucky enough to be naturally muscular, scientists say it might be because you are part Neanderthal.
Researchers from the Max Planck Society found that a genetic change picked up from our ancient Neanderthal relatives makes people noticeably more muscly.
Modern people who inherit the Neanderthal gene from one parent have about 270g more muscle on average.
Meanwhile, people who inherit one copy of the gene from each parent have around half a kilogram more muscle mass on average.
The mutation also gives people wider hips and changes to the jaw that are 'reminiscent of Neanderthals'.
According to the researchers, up to 24 per cent of people carry this unique Neanderthal trait in South Asia.
Meanwhile, just 0.5 per cent of modern Europeans have this muscle–boosting adaptation.
Senior author Dr Hugo Zeberg says: 'It is fascinating that one genetic change inherited from Neanderthals can still have an effect on the human body today.'
If you are naturally more muscular, scientists say that it might be because you have a gene inherited from interbreeding with Neanderthals. Pictured: A reconstruction of a Neanderthal man
The mutation affects how our cells react to growth hormone, a chemical signal that drives childhood growth and tells our bodies to produce more muscle.
Growth hormone is produced by the pituitary gland in the brain, and travels through the body in the blood.
To work, the hormone must first bind to a specialised 'receptor' on our cells, which recognises the signal and activates genes responsible for cell growth.
In their paper, published in the journal Current Biology, researchers discovered that Neanderthals have two important differences in their cells' growth hormone receptors.
Co–author Dr Philipp Kanis told the Daily Mail: 'We found that the receptor variant is more active.
'Meaning, under the same amount of growth hormone, it had a higher downstream effect.'
The researchers tested the effects of this mutation on lab–grown cells, engineered to either have the Neanderthal or modern–human variant.
They discovered that cells with the Neanderthal receptor grew about 40 per cent faster than their Homo sapiens counterparts.
Scientists say that Neanderthals passed on a gene to humans through interbreeding around 47,000 years ago, which gives some people a more efficient response to growth hormone during puberty
Why does this Neanderthal gene make people more muscular?
For growth hormone to trigger cell development, it first has to bind with a receptor on the outside of the cell.
This receptor takes the chemical message from the hormone and activates the genes that control cell growth and development.
Neanderthals have a gene that produces a slightly different growth hormone receptor.
Their receptor is more efficient than the one found in most modern humans, meaning that smaller amounts of growth hormone lead to more activity.
Scientists say that each copy of the gene gives someone roughly 270 grams of extra muscle.
That means someone who inherits a copy from both parents will have around 500 grams more muscle.
From the fossil evidence that has survived, scientists know that Neanderthals were typically more robust and had larger muscles than the average human.
Modern people with the gene also had characteristics that are similar to those found in Neanderthals, such as shorter tooth roots, stronger arms and legs, and larger buttocks.
These differences weren't found in children younger than 11, which suggests that the biggest impacts kick in during the period of rapid growth through puberty.
However, the researchers don't think that Neanderthals' distinct appearance was entirely due to their more efficient growth hormone receptors.
Dr Kanis says: 'There are many genes and genetic variants and other factors that have an impact on morphology.
'We do not claim that we can explain Neanderthal morphology by this single variant. But it is the first time, at least to our knowledge, that we can link certain traits reminiscent of Neanderthals to a specific genetic variant.'
Scientists think that modern humans picked up this gene by interbreeding with Neanderthals about 47,000 years ago.
This is after the main human migrations out of Africa, which explains why the gene is absent in people with African heritage.
The gene is found in up to 24 per cent of people in parts of South Asia, and only 0.5 per cent of people in Europe. Proportion of Neanderthal gene in the modern population shown in red
Meanwhile, the mutation is strikingly common in South Asia for reasons that the researchers don't fully understand.
Dr Zeberg suggests the mutation is so common that it 'might have conferred some advantage'.
However, the gene's concentration could also be due to a 'founder effect', where a small colony starts up a new population, leading to reduced genetic diversity.
While it might seem like people who carry this Neanderthal trait might be better natural athletes, the researchers say this isn't likely to be the case.
Although people with the gene are more likely to put on muscle mass, the researchers note that there are many other genetic and environmental factors that determine strength.
Co–author Miriam Berreiter, a PhD student at the Karolinska Institutet in Sweden, says: 'As someone who does CrossFit, I was delighted to find Neanderthal genetics and muscle mass coming together in the same study.
'But even a Neanderthal growth hormone receptor is no substitute for training.'
A close relative of modern humans, Neanderthals went extinct 40,000 years ago
The Neanderthals were a close human ancestor that mysteriously died out around 40,000 years ago.
The species lived in Africa with early humans for millennia before moving across to Europe around 300,000 years ago.
They were later joined by humans, who entered Eurasia around 48,000 years ago.
The Neanderthals were a cousin species of humans but not a direct ancestor - the two species split from a common ancestor - that perished around 50,000 years ago. Pictured is a Neanderthal museum exhibit
These were the original 'cavemen', historically thought to be dim-witted and brutish compared to modern humans.
In recent years though, and especially over the last decade, it has become increasingly apparent we've been selling Neanderthals short.
A growing body of evidence points to a more sophisticated and multi-talented kind of 'caveman' than anyone thought possible.
It now seems likely that Neanderthals had told, buried their dead, painted and even interbred with humans.
They used body art such as pigments and beads, and they were the very first artists, with Neanderthal cave art (and symbolism) in Spain apparently predating the earliest modern human art by some 20,000 years.
They are thought to have hunted on land and done some fishing. However, they went extinct around 40,000 years ago following the success of Homo sapiens in Europe.
