A paper on SARS-CoV-2 sequencing around the globe reports:
We find that two particular mutation rates, G →U and C →U, are similarly elevated and considerably higher than all other mutation rates, causing the majority of mutations in the SARS-CoV-2 genome, and are possibly the result of APOBEC and ROS activity. These mutations also tend to occur many times at the same genome positions along the global SARS-CoV-2 phylogeny (i.e., they are very homoplasic). We observe an effect of genomic context on mutation rates, but the effect of the context is overall limited. While previous studies have suggested selection acting to decrease U content at synonymous sites, we bring forward evidence suggesting the opposite.Nicola De Maio, Conor R Walker, Yatish Turakhia, Robert Lanfear, Russell Corbett-Detig, Nick Goldman, Mutation rates and selection on synonymous mutations in SARS-CoV-2, Genome Biology and Evolution, 2021;, evab087, https://doi.org/10.1093/gbe/evab087
The paper is open access.
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