This variant is noticeable by the number of mutations that have appeared at the same time and on regions of its genome that are essential to its physiopathology.
23 mutations in total = 14 mutations, 3 deletions, and 6 silent mutations
Spike protein mutation
Several mutations are particularly concerning since they affect the spike protein: indeed, it is this protein which is responsible for the entry of the virus in targeted cells. It is also this protein which induces the synthesis of principal neutralizing antibodies (the protective antibodies that allow not to be reinfected). Finally, it is this same protein which is used in a majority of candidate vaccines, including via the vaccines RNA messengers. Although, so far, there exists no proof of important alterations on the S protein to decrease the immune responses or the vaccines’ efficiency, scientist and doctors are closely watching this mutant.
This mutation modifies the capacity of the virus to enter the cell. Considering the speed of the virus’ spread, it seems that this affinity alteration unfortunately increased. This point is yet to be demonstrated by measuring the infection capacity in the cell culture of a live mutant virus.
Here, again, the mutation affects an essential mechanism in the process of entry of the virus in the cell. It is the first time that researchers find in the same virus these two mutations.
This deletion has already been found in patients in the context of an exhaust immune system during immunotherapy by anti-Sars-Cov2 antibodies.
This region of the genome is also one of the 3 targets of certain PCR reactants such as the thermofisher reactant. In this case, the 3 targets that are searched are the n, orf1 and spike genes. In the case of this variant, the results will be positive only on the n and orf1 genes and negative on the spike. This will not impact the final result: with 2 positive target, the diagnosis is reached. However, this profile must show suspicion of the presence of this variant.
Will these mutations impact the immunitary response?
In other terms, will the neutralizing antibodies obtained after an infection or a vaccination be able to neutralize this variant with the same efficiency? Although there is still no data on the subject, scientists evaluate, seeing the amount of simultaneous mutations, and on key regions of the genome, that the probability of an impact on immunitary response is high.
Furthermore, we know that coronaviruses are viruses that have, progressively with their mutation and evolution, a high capacity to escape the immunitary system. However, the immunitary responses are “polyclonal”, and often affect several targets of the virus, allowing its efficiency despite the mutations on a target.