“A coronavirus epidemic hit East Asia 20,000 years ago”, Health News, ET HealthWorld
The new study suggests that an ancient coronavirus plagued the region for many years, researchers say. The discovery could have disastrous implications for the Covid pandemic if it is not soon brought under control by vaccination. “We should be concerned about this,” said David Enard, an evolutionary biologist at the University of Arizona who led the study, which was published Thursday in Current Biology. Until now, researchers could not go back very far in the history of this family of pathogens.
Enard and his colleagues applied a new research method. Instead of examining the genes of coronaviruses, the researchers looked at the effects on the DNA of their human hosts. Over generations, viruses cause huge changes in the human genome. A mutation that protects against viral infection, it will be passed on to the offspring.
When a new mutation offers resistance to a virus, it can quickly become more common from one generation to the next. And other versions of this gene, in turn, are becoming rarer. So if one version of a gene dominates over all others in large groups of people, scientists know it’s probably a sign of rapid evolution in the past.
Enard and his colleagues compared the DNA of thousands of people in 26 different populations around the world, examining a combination of genes known to be crucial for coronaviruses. In East Asian populations, scientists found that 42 of these genes had a dominant version.
They estimated that these genes developed their antiviral mutations between 20,000 and 25,000 years ago. Scientists looking for drugs to fight the new coronavirus might want to look at the 42 genes that evolved in response to the old outbreak, said Yassine Souilmi, researcher and co-author of the study. nyt