Coronavirus mutations high in Bengaluru

The mutation rate of the coronavirus is high in Bengaluru when compared to the national average, researchers from the Indian Institute of Science (IISc) have found.

The research team, led by Professor Utpal Tatu of the Department of Biochemistry, IISc, found that isolates or viral samples taken from nasal secretions of Covid-19 positive individuals in Bengaluru had over 11 mutations per sample, higher than the national average (8.4) and the global average (7.3), according to a statement by the IISc.

Professor Tatu said these numbers may now vary as the study was conducted last year but was pending peer review since November before being published in the Journal of Proteome Research this February.

“Our findings have been corroborated by developments since,” he said. “For one, we found that a majority of isolates in Bengaluru contained a mutated variant of the novel coronavirus which was named D614G. Now, the D614G variant is the most common variant of the virus in Bengaluru.”

But can the city’s mutation rate mitigate the effectiveness of vaccinations or drive a new Covid resurgence? “The verdict is still out,” he said.

However, in another paper, researchers from the Institute of Genomics and Integrative Biology (CSIR-IGIB) recently studied 146 unique novel coronavirus variants for “escape mutations,” which gives some variants the ability to “evade” antibodies that can kill them. Vaccines work by triggering an antibody response.

Concern has grown over one such escape variant, the N440K. “As per the latest information, the N440K variant has been found in large numbers in Karnataka,” Adjunct Professor Vinod Scaria of CSIR-IGIB said.

The pace of mutations means better testing methods are needed, Professor Tatu said, adding that his team used “proteo-genomic” investigation. The genomic analysis used next-generation sequencing (NGS), a technology that allows for rapid sequencing of the entire genome.

During their analysis on how people respond to the virus, the IISc team also considered host proteins. They discovered 441 proteins unique to Covid-19 positive patients, many of which are speculated to play a key role in the body’s immune response.