Three genes derived from Neanderthals reduce the risk of Covid-19 by 22 percent, a new study has revealed.
The genes sit side by side on chromosome 12, and this large piece of genetic material contains 75,000 individual pieces of DNA.
Researchers compared the DNA of 2,200 Covid-19 patients from around the world with the genes of three Neanderthals that lived 50,000, 70,000 and 120,000 years ago.
They found that people with Neanderthal versions of the OAS1, OAS2 and OAS3 genes were less likely to develop adverse symptoms after being infected with the coronavirus.
These genes secrete an enzyme that specifically targets invading RNA viruses, and the Neanderthal version is thought to be more potent.
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A previous study has found eight genetic locations spread across five chromosomes (3, 6, 12, 19 and 21) that are ‘associated with the risk of requiring intensive care of SARS-CoV-2 disease’. However, the new analysis shows that only those found at chromosome 3 and 12 are derived from Neanderthals (pictured). Chromosome 12 contains three genes that help fight Covi and reduce the risk of serious infection by 22%
Professor Hugo Zeberg and Dr. Svante Pääbo from the Karolinska Institute in Stockholm and the Max Planck Institute for Evolutionary Anthropology in Leipzig, respectively, conducted the study.
A previous study has found eight genetic locations spread across five chromosomes (3, 6, 12, 19 and 21) that are ‘associated with the risk of requiring intensive care of SARS-CoV-2 disease’.
However, the new analysis shows that only those found at chromosome 3 and 12 result from a hybrid transfusion between Homo sapiens and Neanderthals.
Researchers compared the DNA of 2,200 Covid-19 patients from around the world with the genomes of three Neanderthals that lived 50,000, 70,000 and 120,000 years ago. They found that people with neanderthal versions of the OAS1, OAS2 and OAS3 genes were less likely to develop adverse symptoms after being infected with the coronavirus
The chromosome 3 gene was the subject of a previous study from the same team of experts.
He published the Neanderthal version, which is present in about one in eight people today, in fact doubling the risk of needing intensive care if one catches Covid.
But the fragment of Neanderthal DNA on chromosome 12 is more common.
It was present in about one in ten that lived more than 20,000 years ago, and then rose to about 15 percent up to 10,000 years ago.
The researchers believe that it will continue to gain more control, with about a third of people living between 3,000 and 1,000 years ago.
Pictured, the percentage of people in Eurasia with the Covid fighting genes on chromosome 12 over time. It is now more than 30 percent but experts say it often reaches and exceeds 50 percent in some numbers
In the picture, a map of the world shows the percentage of people who have the Neanderthal versions of the OAS1, OAS2 and OAS3 genes (red portions of ringworm). Because of the ancient patterns of Neanderthals migration and the fact that few people lived in Africa before their extinction, very little Neanderthal DNA can be seen in people living in sub-Saharan Africa today. .
Interestingly, the current allele frequency in Eurasia is around 30 percent, suggesting that the Neandertal haplotype may have risen in frequency relatively recently, ‘the researchers said writing in their paper.
They say: ‘It is present in numbers in Eurasia and America at behavioral frequencies that often reach and exceed 50 percent.’
Dr Pääbo says it is ‘remarkable’ that two Neanderthal variants can have such different effects on the human immune response to SARS-CoV-2 disease.
‘This shows that our heritage from Neanderthals is a two-edged sword when it comes to our response to SARS-CoV-2,’ adds Professor Zeberg.
The researchers believe that the positioning of Neanderthal DNA on chromosome 12 is crucial, as it contains three genes (OAS1, OAS2 and OAS3) that play a crucial role in fighting disease.
In particular, they help produce enzymes that target and destroy invasive RNAs, such as Covid-19-induced SARS-CoV-2.
The new research, published in the journal PNAS, found that the Neanderthal variant produces more virus-fighting enzymes than the island variant Homo sapien.
They may be speculating that when modern humans encountered new RNA viruses outside Africa, higher enzymatic activity of the ancestral variables they acquired through genetic interaction with Neandertals may be be beneficial, ’the researchers write.
Interestingly, there is evidence that the Neanderthal-like OAS haplotype may have recently increased in Eurasia, suggesting that selection may have a positive effect on the Neandertal-derived OAS locus in the Eurasia. last thousand years. ‘
Because of the ancient patterns of Neanderthals migration and the fact that few people lived in Africa before their extinction, very little Neanderthal DNA can be seen in people living in sub-Saharan Africa today. .
In fact, the researchers say Covid ‘s Neanderthal fighting genes are’ almost completely absent ‘from these numbers.
‘In America, it occurs in lower frequencies in some populations of African ancestry, possibly as a result of gene flow from populations of European or Native American ancestry,’ they add to the paper.
The latest study supports previous findings from an individual team of Canadian researchers, who also concluded that the OAS1 gene reduces the risk of serious illness, hospitalization and death from Covid-19 .
Although they did not look at the origin of the gene, they found five genes that increase the incidence of malignancy.
Four of these genes – TYK2 and DPP9 on chromosome 19; IFNAR on chromosome 21 and OAS on chromosome 12 – were analyzed by the most recent study.