Public Health England has announced the discovery of another mutation in the UK coronavirus variant – the E484K mutation.
It is now common knowledge that mutations are a normal occurrence in viruses. They can either result in the virus becoming more dangerous, or weaker. However, discovery of the E484K mutation in the UK coronavirus variant has put authorities on high alert.
The UK coronavirus variant, called B.1.1.7, was first identified in September of last year in Kent, England. It featured the N501Y mutation, which allows the virus to bind more strongly to host cells. Authorities soon announced that the variant was 70% more transmissible than the previous strain. This led to the implementation of severe lockdown measures across the country. Later on, a report released in January stated the virus was about 30% deadlier.
Now, a recent report by the Public Health England (PHE) has announced the discovery of a new mutation in the UK coronavirus variant. According to the report, researchers identified 11 samples with the new mutation from a total of 214,000 samples that underwent genetic sequencing. Known as E484K, the mutation is also present in the Brazilian and South African variants. However, researchers believe the mutation emerged separately in the UK variant.
The E484K mutation has now been identified in a small fraction of viruses carrying sequence differences defining the UK variant. This suggests that the UK variant is now independently acquiring the E484K change.
Dr. Jonathan Stoye, Francis Crick Institute.
The Vaccine-Evading Mutation
So far, researchers have discovered a total of 40 cases with the new mutation. Around 32 of these cases occurred in Liverpool, where the mutation was seen in the original coronavirus.
According to research, the E484K mutation affects the receptor-binding domain (RBD), where antibodies produced in response to infection binds to the virus. However, once this site is altered the neutralizing antibodies are unable to attach to the virus. Thus, helping the virus evade the body’s natural defense and render vaccines ineffective.
There is also concern that the South African variant might be able to more efficiently re-infect individuals who have previously been infected with the original form of the virus. This is likely to be due, in part, to the E484K mutation which may weaken the immune response and also impact the longevity of the neutralizing antibody response. So B.1.1.7 variants carrying the E484K mutation may be more efficient at re-infection.
Prof Lawrence Young, University of Warwick
Recently, the Novavax COVID-19 vaccine reported a 60% efficacy against the South African variant. Johnson & Johnson also revealed a lower vaccine efficacy against the variant in its vaccine’s phase 3 trials. Both these findings point to the E484K mutation’s ability to evade vaccines. However, it is still unclear how well the currently approved vaccines work against the new variants. It is too early to predict how the recent mutation will affect the UK coronavirus variant.
Despite strict lockdown measures the virus continues to evolve. At the moment, widespread vaccination programs remain the best way to contain the spread of the virus.
Reference:
Public Health England
Greaney AJ, Starr TN, Gilchuk P, et al. Complete Mapping of Mutations to the SARS-CoV-2 Spike Receptor-Binding Domain that Escape Antibody Recognition. Cell Host Microbe. 2021;29(1):44-57.e9. doi:10.1016/j.chom.2020.11.007
