Explainer: Why the COVID-19 coronavirus was not made in a lab2020|01:33
The novel coronavirus did not originate from a research laboratory, according to a study published in Nature Medicine. Researchers say the novel coronavirus was not made in a lab, after comparing its RNA sequence to SARS, MERS and other coronaviruses including the HKU1, which is known to cause mild symptoms in humans. Citing the authors, Live Science reports the study focuses on the novel coronavirus's spike protein.The protein consists of receptor binding domains, also known as RBDs, and a cleavage site.The RBD hooks on to an ACE2 receptor on the surface of human cells, then the cleavage site opens the receptor for the virus to enter.The spike protein design is deemed so effective that it could only have resulted from natural selection and not human engineering.When scientists simulated the virus in computer models, they found computers to underate COVID-19's infectiousness by a significant margin.Study co-author Kristian Andersen of Scripps Research was cited as saying if scientists designed the virus, they would not have chosen the spike protein mutations that seemed ineffective.Additionally, biological weapons were usually created from deadly viruses, but SARS-CoV-2's close relatives are bat and pangolin viruses that are largely innocuous.The virus is speculated to have spread from bats to pangolins to humans. According to the researchers, they are working to determine at what point SARS-CoV-2 developed the cleavage site mutations that increased its infectiousness.