Selective pressure is contributing to faster development of Covid-19 variants

Professor Sergei Pond

Professor Sergei Pond is part of an international team publishing research suggesting that new conditions are contributing to the faster development of variants of the Covid -19 virus.

Titled “The emergence and ongoing convergent evolution of the SARS-CoV-2 N501Y lineages,” the paper appears in Cell, a peer-reviewed journal. Pond and his Temple colleagues collaborated with scientists at the University of Cape Town in South Africa. University of Glasgow in the United Kingdom, Pennsylvania State University and several other research institutions.

According to Pond, “selective pressure” on the virus can allow for faster-developing variants. “Selective pressure is an evolutionary force that promotes, or suppresses, certain genetic changes. In this case, the selective force that appeared in the fall of 2020 was most likely an immune response in individuals who had been infected with, and recovered from, earlier strains that same year,” says Pond. “These forces remain today, and they are also augmented by selective forces exerted by the immune systems of vaccinated individuals with breakthrough infections.”

“This is called convergent evolution,” explains Pond, a professor of biology and researcher at the College of Science and Technology’s Institute for Genomics and Evolutionary Medicine (iGEM). “The virus is going to the similar target (in humans) through similar pathways. It means that we can try to predict a little bit of what the virus is going to do in the future. As you might imagine this is a highly relevant question because everybody wants to know what’s going to happen next.” 

Steven Weaver, senior programming analyst at iGEM, Stephen Shank, senior software developer at iGEM, and Alexander Lucaci, a bioinformatics graduate student, are also authors on the Cell paper.

Asked for comment on the Omicron variant, Pond says: “This viral strain is taking a different evolutionary route compared to Alpha, Beta, Gamma, and Delta lineages. We are actively investigating its evolutionary history, but it is already clear that the virus has acquired a large number of mutations not previously seen in combination in any of the 5+ million sequenced strains. One thing is for certain: viruses always have new tricks up their sleeves.”

-Jon Caroulis

Posted: 
December 8, 2021