A resulting spread of Neanderthal DNA spread far and wide through our population as it passed through generations, while Neanderthals themselves became extinct. About 50 percent of people in South Asia and 16 percent of Europe now carry this length of DNA, which scientists have now linked to the most severe form of COVID-19.
According to new research, people who have this genetic inheritance are three times more likely to have mechanical ventilation before contracting the virus, explains evolutionary anthropologist Hugo Zeberg from the Max Planck Institute for Evolutionary Anthropology in Germany.
Scientists are beginning to understand that some people are more vulnerable to SARS-COV-2 than others. The disease has now killed more than one lakh people.
While contributing to pre-existing underlying conditions and social asymmetries, a large part of our vulnerability is explained, yet a significant part of stubborn people who are young and healthy yet inexplicably end up with severe respiratory problems. Occur, while their equally healthy only experience mild symptoms.
Zeberg and geneticist Swante Pebabo of the Okinawa Institute of Science and Technology in Japan analyzed genetic data from 3,199 hospitalized COVID-19 patients and observed that some gene variants on chromosome 3 are found together in populations, such as That they were random mutations.
Such a length of DNA, the spread of six genes and 49.4 thousand bases passing together suggests that this variation was introduced simultaneously into the human genome, meaning it was inherited.
Previous research linked this gene region to patients who had a severe reaction to SARS-CoV-2 who needed to be hospitalized.
Hence Zeberg and Pääbo examined our extinct human relatives to see where the length of this gene came from. They did not find any of these specific gene variants in the Denisovan genome, and some of them were found in two Neanderthals in Siberia. But a Neanderthal from Croatia shared the most similarities.
The researchers wrote, “These results are consistent with this Neanderthal being close to the majority of Neanderthals who contributed DNA to present-day people.”
Zeberg and Pääbo calculated that it was highly unlikely that this combination of genes came from the shared ancestors of both humans and Neanderthals, meaning they were introduced when our two species intervened.
We do not yet know that this snippet of chromosome 3 increases the risk of severe disease.
“This is something that we and others are now investigating as soon as possible,” Pabu explained.
The team suspects that in the past these genes may prove to be an advantage for some people – perhaps against another pathogen. A previous study indicated that Neanderthal DNA may provide protection from ancient viruses.
This may explain why the unfortunate version of chromosome 3 is now prevalent in some populations, such as in Bangladesh, where 63 percent of people have it, but it is almost absent in others, such as Africa.
This distribution may explain that people of Bangladeshi ancestry in Britain are twice as likely to die from COVID-19 than the rest of the population.
“It is striking that genetic inheritance from Neanderthal has such tragic consequences during the current epidemic,” Pabu said.
Last week, another team identified a possible immune system that may also contribute to severe coronovirus cases.
While these genetic pieces of the coronavirus puzzle end up fitting together, it’s important to remember that environmental factors also play a big role, regardless of where we contracted the disease in the first place – and it’s something over which we have control today is.
This research was published in Nature.