The researchers in a paper, titled, ‘The Proximal Origin of SARS-CoV-2’, analysed public genome sequence data from SARS-CoV-2 and related viruses.
A corresponding author of the paper, Dr Kristian Andersen, said, “By comparing the available genome sequence data for known coronavirus strains, we can firmly determine that SARS-CoV-2 originated through natural processes.
According to sciencedaily.com, the researchers noted that coronaviruses were a large family of viruses that could cause illnesses ranging widely in severity.
“The first known severe illness caused by a coronavirus emerged with the 2003 Severe Acute Respiratory Syndrome epidemic in China. A second outbreak of severe illness began in 2012 in Saudi Arabia with the Middle East Respiratory Syndrome,” the researchers wrote.
The scientists analysed the genetic template for spike proteins, armatures on the outside of the virus that it uses to grab and penetrate the outer walls of human and animal cells.
“More specifically, we focused on two important features of the spike protein; the receptor-binding domain, a kind of grappling hook that grips onto host cells, and the cleavage site, a molecular can opener that allows the virus to crack open and enter host cells.
“We found that the receptor-binding domain portion of the SARS-CoV-2 spike proteins had evolved to effectively target a molecular feature on the outside of human cells called ACE2, a receptor involved in regulating blood pressure. The SARS-CoV-2 spike protein was so effective at binding the human cells.”
The scientists concluded it was the result of natural selection and not the product of genetic engineering that gave birth to coronavirus.