People who carry a version of a gene inherited from Neanderthals have a lower risk of serious illness, hospitalization and death from Covid-19, a new study finds.
The gene, known as OAS1, was introduced into the human genome after our ancestors mated with the now-extinct human relative about 60,000 years ago.
The OAS1 gene controls a protein of the same name, which is involved in the body’s response to viruses.
The version inherited from Neanderthals is less common in society, but offers more protection against the coronavirus, researchers say.
The finding contradicts previous research, which found that a cluster of hereditary Neanderthal genes may increase the risk of becoming seriously ill from Covid-19.
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A specific version of a gene, known as OAS1, inherited from Neanderthals reduces the risk of serious illness, hospitalization and death from Covid-19, a new study finds.
The study, led by McGill University in Canada, looked in detail at the genetic code that produces different versions of OAS1.
One position within the gene, known as rs10774671, has two main forms. The most common form is variant ‘A’, but the ancestral version of Neanderthals is called variant ‘G’.
“The ancestral variant (rs10774671-G) is the major allele in African populations and has been fixed in Neanderthal and Denisovan genomes,” the researchers write.
The difference between the two gene variants is that A results in many different types (or isoforms) of OAS1 protein being produced in different amounts, while type G results in a large amount of one specific isoform of the OAS1 protein called p46.
‘How much each of us has of either isoform appears to be determined by a single change in the genetic code of the protein-coding gene, that is, the area in the genome that contains the blueprint to build this protein’ study author Dr. Pietzner of Cambridge University told MailOnline.
The p46 version of the protein is longer than the others and has higher antiviral activity than other types of OAS1, the researchers say.
When people have high levels of the p46 version of OAS1, which is made by the Neanderthal gene, they have less than a third of the risk of becoming infected as someone with low levels of p46 OAS1, the data suggests.
And if they do become infected, these people have only nine percent of the risk of hospitalization and five percent of the risk of developing “very serious” Covid as someone with low p46 levels.
This gene embedded itself in human genomes after our ancestors mated with the now-extinct human relative that lived about 60,000 years ago
The G form of the gene originally entered Homo sapiens through our predecessor’s dalliances with our sister species millennia ago, and has survived to this day.
It took so long for its ability to fight disease and provide a survival benefit.
“This protective form of OAS1 is present in Sub-Saharan Africans, but was lost when the ancestors of modern Europeans migrated from Africa,” co-author Brent Richards of the Jewish General Hospital and McGill University in Montreal told Reuters.
“It was then reintroduced to the European population by mating with Neanderthals.”
The researchers believe that drugs that target the OAS1 gene and increase the amount of p46 in the system could lead to effective treatment of Covid-19.
A previous study from the University of Edinburgh identified five genes that could negatively affect a patient’s chances of survival after catching Covid-19.
One was the regular version of OAS1 (variant A), which reinforces the suggestion that the type of OAS1 gene a person inherits may play an important role in disease progression and severity.
Meanwhile, a previous study found that some genes inherited from Neanderthals can negatively impact the survival rates of coronavirus patients.
Researchers from Germany and Sweden found that a specific cluster of Neanderthal genes was associated with an increased risk of Covid-19 death.
In a study of 3,199 hospital patients with the coronavirus in Italy and Spain, they found that this genetic signature was linked to a more serious disease.
They found that people who developed Covid-19 so bad that they needed a ventilator were 70 percent more likely to have genetic variation.