They were tough, you might think – but the Neanderthals had a low pain threshold compared to modern humans, according to a study: A gene that is linked to the transmission of pain sensations in the nervous system showed “reinforcing” in our archaic cousins “Mutations on. The researchers were also able to show that people today who inherited this gene variant from the Neanderthals are actually comparatively sensitive to pain. To what extent the Neanderthals reacted just as sensitively remains questionable. Because the sensation of pain is also processed in the brain, they indicate.
It was a bang in the history of anthropology: the analysis of fossil DNA from the remains of Neanderthals showed that our archaic cousin was not really extinct – he lives on in us. A few percent of the Neanderthal genome in many people today documents a former mix of the two human species. Some studies have already examined the importance of the genetic heritage of the Neanderthal man in today’s people. Accordingly, Neanderthal gene variants are linked, for example, to lighter skin and hair color, influence the metabolism and can play a role in the immune system. A study recently found that DNA sections inherited from the Neanderthals could even favor severe Covid 19 courses.
A special “pain protein” in sight
As the researchers led by Svante Pääbo from the Max Planck Institute for Evolutionary Anthropology in Leipzig report, they have now discovered another genetic peculiarity of the Neanderthal man, which apparently still shapes the genome of some people today: they came across three in the sequenced genomes of the Neanderthal man Mutations in a gene encoding the NaV1.7 protein. The characteristics of the gene variation indicate that all Neanderthals owned it.
As the researchers explain, the protein forms a so-called ion channel, which controls in the nerves whether and to what extent painful signals are passed on to the spinal cord and brain. The importance of NaV1.7 is considerable: It is known that certain mutations in the gene and thus in the protein that is formed lead to pathological insensitivity – while others lead to chronic pain.
To investigate how the mutations in the Neanderthal gene change the nerves, the researchers created the special version of NaV1.7 in cell cultures. The studies of the protein showed: “The Neanderthal variant of the ion channel shows three amino acid differences compared to the usual ‘modern’ variant,” says the study’s first author, Hugo Zeberg from the Karolinska Institute in Stockholm. Neurophysiological studies at the molecular level then showed that the Neanderthal ion channel is activated comparatively easily. This shows that the peripheral nerves in Neanderthals were more sensitive to pain stimuli than in modern humans, the scientists explain.
Were Neanderthals particularly sensitive to pain?
Next, they investigated whether there are peculiarities in the sensation of pain in people today who have inherited the Neanderthal gene. They used the data from an extensive population study in Great Britain, which includes genetic data as well as information about pain symptoms. It was shown that around 0.4 percent of the approximately 500,000 British people carry a copy of the Neanderthal gene variant in the genome. The comparison with the information on the pain symptoms then showed: The probability that these carriers reported pain was about seven percent higher than in people without the genetic peculiarity.
“The extent to which people feel pain is primarily dependent on their age. People who have the Neanderthal version of the ion channel feel more pain – about as if they were eight years older, ”says Zeberg. “While individual amino acid substitutions do not impair the function of the ion channel, the complete Neanderthal variant with three amino acid substitutions leads to increased sensitivity to pain in people living today”, the scientist summarizes the result of the genetic research.
But does that mean that the Neanderthals were “sensitive” compared to modern humans? In this context, it is important to emphasize that pain sensation is not necessarily a problem. Because it fulfills a vital protective function against potentially harmful influences on our body. “This study only shows that the threshold for triggering pain impulses was lower in Neanderthals than in most people living today,” says Pääbo. “It is not clear whether they actually felt more pain because pain is also modulated in the spinal cord and brain,” the anthropologist points out.
Source: Max Planck Institute for Evolutionary Anthropology, professional article: Current Biology, doi: 10.1016 / j.cub.2020.06.045