Raul Rabadan: Recombination and lineage-specific mutations led to the emergence of SARS-CoV-2

The SARS-CoV-2 virus is continually mutating, with about one amino acid substitution occurring every week. Additionally, recombination that occurs when there is co-infection of two different viruses is also a significant contributor to the evolution of the virus.

Work by Dr. Rabadan suggests that, although SARS-CoV and SARS-CoV-2 appear only distantly related based on overall sequence, about 10-15 years ago, there was recombination of two viruses that created the ancestor of SARS-CoV-2. The SARS-CoV-2 ancestor likely took part of the receptor binding domain from SARS, enabling it to bind to human ACE2 receptor. Further mutation then allowed for higher binding affinity and refined interactions with the receptor.

This two-hit model helps explain the ability of SARS-CoV-2 to cause COVID disease, and emphasizes the important role animal reservoirs of these viruses can play in facilitating the development of human pathogenesis.

свернуть