The mutation in the spike protein of circulating #SARSCoV2 has been the focus of many stories over the last couple of days. We and others have shown that coronaviruses exist as mixed populations (quasispecies) in a host.. here’s what we know.
A THREAD..
#mutantcovid

We showed that MERSCoV can select for different variants in cells from an alternate host (I.e. bats): https://www.nature.com/articles/s41598-020-64264-1

So, what we realized is that the virus itself doesn’t actively change, but the major represented population does, based on selection pressure. So what does that mean?...

Let’s say a coronavirus exists as different variants - A+B+C.
The variants exist in different quantities - 4A + 2B + 1C. Now when you sequence a patient sample, your sequencing is likely to pick up the most represented variant - in this case: 4A.

As the virus circulates, due to multiple factors, this ‘represented’ population may evolve and change to become 2A + 4B +2C. Thus, if you sequence this sample from a patient - your sequence will likely represent identify 4B as the circulation strain.

Thus, the existence of #SARSCoV2 as quasispecies is not surprising. Mutations within spike are concerning because current vaccines induce antibodies against spike. But as noted by other experts, one or two amino acid changes within spike ‘May not’ affect antibody binding.