Genes inherited long ago from Neanderthals may influence whether someone will have severe COVID-19, the New York Times reports.
A recent paper appearing in the New England Journal of Medicine not only tied the ABO blood locus group to COVID-19 severity, but also implicated a gene cluster on chromosome 3. In a new analysis, posted as a preprint to BioRxiv, researchers from the Max Planck Institute for Evolutionary Anthropology trace this gene cluster back to Neanderthals.
In their analysis, Max Planck's Hugo Zeberg and Svante Pääbo note that the genes in the cluster on chromosome 3 are in high linkage disequilibrium with one another and span nearly 50 kilobases, suggesting the haplotype is due to positive selection, low recombination at that site, or introduction via gene flow from Neanderthals or Denisovans.
They found the lead risk variant was present in a Neanderthal who lived some 50,000 years ago in Croatia. Additionally, they report this variant is present in about 30 percent of people of South Asian ancestry and in about 8 percent of people of European ancestry.
But just what the variant does is unclear. Geneticists tell the Times that the variant may have initially been beneficial and perhaps even helps people cope with other infections, but now, with COVID-19 could contribute to the immune system overreaction seen in severe cases.
"One should stress that at this point this is pure speculation," Zeberg cautions at the Times.