COVID-19 virus mutation, is it something worth to be worried about?

Virus is heavily dependent on the host for its spread and survival, so it must constantly come up with other versions of itself – mutate – to avoid getting eradicated by the host’s immune system. Viruses also need to evade the mechanisms of the vaccines that we develop. Mutation of viral genome is natural; it’s what they do.

Virus is broadly categorized into RNA and DNA virus based on the type of genome they carry. DNA virus is slow to replicate and has a lower mutation rate relative to RNA virus. As for RNA virus, its fast replication allows for a greater mutation rate.

This is because DNA virus has machineries to proofread replicated genomes, which RNA virus does not have. So even if replication machineries of RNA virus make errors, they simply do not have the necessary mechanism to correct the mistakes.

The novel coronavirus that has spread all around the globe is an RNA virus. This is the point the fear of viral mutation into a deadlier strain is revolving around.

Just like the novel coronavirus, influenza virus – more commonly known as flu virus – also is an RNA virus. As we all know, influenza virus mutates so fast that scientists have to adjust vaccines annually.

However, scientists state that mutation rate of the new coronavirus will not be as fast as that of influenza.

For an RNA virus to mutate, its protein structure necessary for the survival of the virus needs to change. This means that the virus’ genome sequence needs to mutate, causing variations in the RNA base sequences. RNA virus has Adenine, Uracil, Guanine, and Cytosine as its base, and three base sequences make up one amino acid.

Although its base sequences have changed over time, COVID-19 virus needs to mutate in a way that would make an impact on protein structures that determine its pathogenicity.

Novel coronavirus has a genome sequence from 1 to 29903, and scientists found approximately 6000 points where the viral genome has been mutated. Vaccines that are being developed target the genomic sequence from 21563 to 25384. Although there have been findings that shows 700 or so mutations within that specific region, the influence of the mutation on the developing vaccines is minimal.

Scientists around the world are collaborating on GISAID (https://www.gisaid.org/) to create an accurate genealogy of the novel coronavirus, and are working around the clock to monitor mutations.

References:
kobic (https://www.kobic.re.kr/covid19/)