Now it turns out that some B.1.1.7 coronaviruses in Britain also have the E484K mutation.
To search for new mutations, British researchers reviewed the 214,159 genomes of coronaviruses that the United Kingdom has sequenced as of Jan. 26. In its report, Public Health England said that they found 11 samples of the B.1.1.7 variant that also had the E484K mutation.
Since that analysis, more of these viruses have come to light. NextStrain, a website where scientists gather and analyze coronavirus genomes, now identifies 16 B.1.1.7 variants that carry the E484K mutation.
These B.1.1.7 coronaviruses gained the mutation thanks to random copying errors as they multiplied inside of people. The evolutionary tree of the coronaviruses suggests that 15 of the variants descend from one common ancestor that gained the E484K mutation. Meanwhile the sixteenth variant seems to have gained the same mutation on its own.
Commenting on Monday’s report, Kristian Andersen, a virologist at Scripps Research Institute in La Jolla, Calif., said that it was impossible yet to say whether the E484K mutation would make these coronaviruses not only more contagious but more resistant to vaccines. “It’s much too early to speculate whether it will, so we’ll have to wait for data,” he said.
Just because the E484K mutation helps the B.1351 variant, the one initially found in South Africa, evade antibodies doesn’t mean it will do the same in other variants. That’s because mutations don’t have a fixed effect. The impact of a single new mutation to a virus depends on the other mutations that the variant already carries.
But in a report posted online Tuesday, Rajiv Gupta, a virologist at the University of Cambridge, and his colleagues reported an experiment they ran to address exactly this question. They combined the E484K mutation with other key mutations found in the B.1.1.7 variant, the one initially found in Britain. The addition of the E484K mutation made it difficult for antibodies to block the viruses. The researchers wrote that they “observed a significant loss of neutralizing activity.”
However, Dr. Gupta and his colleagues used antibodies taken from people who had received just the first of two doses of the Pfizer-BioNTech vaccine. It remains to be seen whether the B.1.1.7 variant with the new mutation, E484K, can evade antibodies after a full vaccination.