Mutant menace

New variants of Covid-19 virus may hamper efforts to create a vaccine

- POOJA BIRAIA JAISWAL

AS COVID-19 continues to spread its tentacles across the globe, some scientists are theorising that the virus, also dubbed as SARS-CoV-2, is mutating. Understanding these mutations, which are essentially small genetic changes or “errors” in the entire genome of a virus made up of 30,000 letters, is significant for the development and evaluation of new diagnostics, drugs and vaccines.

According to a study from the Los Alamos National Laboratory in New Mexico (that has not yet been peer-reviewed), there exists a potentially more transmissible or contagious strain of the SARS-CoV-2 virus due to a mutation to the spike protein (S protein)—that mediates virus entry into host cells—called D614G. As per the study, the mutation Spike D614G is of urgent concern. It began spreading in Europe in early February. When introduced to new regions, it rapidly became the dominant form. Although the observed diversity among the SARS-CoV-2 pandemic sequences is low, its rapid global spread provides the virus with ample opportunity for natural selection to act upon rare but favourable mutations.

Spike protein is the main target of antibodies, and many vaccines are developed based on it. Mutations in virus may hamper the protection induced by a vaccine based on one variant of the spike protein.