Protein inherited by humans from neanderthals linked to reduced COVID-19 severity: Study

Increased levels of a protein, which humans have inherited from neanderthals, are associated with reduced disease severity in COVID-19 patients, according to a study that may lead to the development of new therapeutics against the novel coronavirus infection.

The research, published in the journal Nature Medicine on Friday, noted that the protein OAS1 is linked to less severe disease requiring ventilation and reduced mortality among COVID-19 patients, and may help develop potential therapies to treat those infected with the virus.

"Our analysis shows evidence that OAS1 has a protective effect against COVID-19 susceptibility and severity," explained Brent Richards, study senior author from Lady Davis Institute (LDI) in Canada.

"This is a very exciting development in the race to identify potential therapies to treat patients because there are already therapies in pre-clinical development that boost OAS1 and could be explored for their effect against SARS-CoV-2 infection," Richards said.

In the study, the scientists explored proteins detectable in the blood as a potential drug target against COVID-19.

However, the researchers said they faced several hurdles in determining which proteins play a causal role in disease progression, and which were influenced by COVID-19 itself or other confounding factors.

Applying latest technology for isolating and measuring hundreds of circulating proteins at once, along with genetic analyses, they found that increase in OAS1 levels was associated with reduced COVID-19 death or ventilation, hospitalisation, and susceptibility in up to 14,134 COVID-19 cases and 1.2 million controls.

When they measured levels of this protein in 504 patients with different COVID-19 outcomes, they found that its increased levels in post-infection patients were linked to protection against very severe COVID-19, hospitalisation, and susceptibility.

"The protective effect was particularly large such that we observed a 50 per cent decrease in the odds of very severe COVID-19 per standard deviation increase in OAS1 circulating levels," said Sirui Zhou, study co-author from LDI.

"Interestingly, for non-African peoples, this protective effect is likely inherited from a Neanderthal derived form of OAS1 called p46," Zhou added.

The scientists believe this form of OAS1 likely emerged in people of European ancestry through interbreeding with Neanderthals tens of thousands of years ago.

They said the protein is now detectable in more than thirty-percent of people of European descent.

According to the researchers, this form of the protein may have likely served as protection against earlier pandemics.

They call for further studies on medications that trigger increased OAS1 levels for their effect on COVID-19 outcomes.