The circulating delta strain of coronavirus in Japan could have accumulated too many mutations in one of its non-structural proteins, which over time could deprive it of the ability to “fix” and thus lead to “self-destruction”, according to a group of scientists from the National Institute of Genetics and Niigata University.
“The delta variant of the coronavirus in Japan was transmitted at a high rate and supplanted other variants. But as mutations accumulated in it, we believe it became defective and unable to make its copies. Given the fact that the number of new cases does not grow, we think that at some point, through these mutations, it directs itself directly on the path to natural self-destruction,” said the head of the team of scientists, Professor Itsuro Inoue, in an interview with The Japan Times.
According to the study, a significant part of the mutations in the delta strain in Japan occurred in the A394V region of the nsp14 non-structural protein, which is responsible for the virus’s ability to “correct” existing errors and deficiencies.
“If the virus were” alive and well, “then there would be an increase in the number of new cases, since wearing masks and vaccination cannot prevent infection in some cases even after full vaccination,” the scientist added.
Another Japanese scientist, professor of the Faculty of Medicine at Shimane University Takeshi Urano, responding to a request from the publication to comment on the discovery of Inoue’s team, said that the nsp14 protein does indeed have a vital function of protecting the virus nucleic acids from destruction.
“Studies have shown that a virus with a damaged nsp14 protein significantly loses its ability to reproduce, so this may be one of the factors behind the sharp drop in the number of new infections,” – said the expert, adding that “a reagent that can” tame “this protein could be a potential drug. “
According to Professor Inoue, a similar sharp decrease in new infections may occur in other countries. Still, currently, no other country in the world has recorded as many mutations in the A394V region of the nsp14 protein as in Japan.
At the same time, the specialist warned that the “self-destruction” of the delta variant of the coronavirus in Japan could lead to other active strains entering the country.
“Other strains infiltrated little by little, but the delta strain held them back. And when there is nothing to protect the border, there is an opportunity for new strains to take root since vaccination alone is not the solution to the problem,” said Inoue.