Recent news reports have included speculation that the SARS-CoV-2 virus is ‘mutating’ and ‘evolving’ amid increasing concern that the outbreak could present an even more significant threat than it does already. At present there is no evidence to think that this is the case.
Don’t be scared of mutation. Mutations happen all the time at a relatively constant rate for a specific pathogen, and they are a natural consequence of the process of genome replication. Mutation in this context is a random mistake that gets made when the virus is copying its genome and so the new genome is slightly different. The new mutated genome might be better at transmitting than the old one, or worse, or pretty much the same. We really cannot tell by just looking at new genomes as they come in.
This might mean they are more distantly related to the rest of the outbreak, although some genomes will have more mutations simply by chance. It might also reflect laboratory errors. At present the genomes are distinguished by a few handfuls of mutations, and so any mistakes in the sequencing will have a proportionately large impact. There are also different sequencing technologies being used, some of which have higher error rates than others. A more complete picture of the genetic relationship between different isolates needs a more representative sample of the viral population.
Read more at the Center for Communicable Disease Dynamics