HOW ARE NEW COVID VARIANTS GENERATED? HIDDEN MECHANISM REVEALED
One of the biggest advantages that the SARS-CoV-2, the virus that triggered the Covid-19 pandemic, had was the intense pace at which it would mutate into new variants wreaking havoc globally, killing millions across the world.Â
Scientists have now developed a new technology that has uncovered the underlying mechanism that has enabled them to calculate SARS-CoV-2's mutation rate.Â
In a study published in Nature Microbiology, researchers at Baylor College of Medicine have detailed the development of a new technology called tARC-seq, which revealed a genetic mechanism affecting SARS-CoV-2 divergence.Â
Using the new technology, the team also captured new mutations in SARS-CoV-2 in infected cells in the lab that recapitulated observations revealed by worldwide pandemic viral sequencing data.Â
"The SARS-CoV-2 virus uses RNA, instead of DNA, to store its genetic information. Our lab has long been interested in studying RNA biology, and when SARS-CoV-2 emerged we decided to investigate its process of RNA replication, which is typically error prone in RNA viruses," said corresponding author Dr. Christophe Herman.Â
Researchers aimed to track RNA replication errors in SARS-CoV-2 to understand its evolution and adaptation in human populations. Existing methods struggled to detect rare mutations in samples with low virus counts.Â
Herman, from the Dan L Duncan Comprehensive Cancer Center, introduced Targeted Accurate RNA Consensus sequencing (tARC-seq). This technique accurately identifies RNA replication errors in low-abundance samples.
Initially, it was believed SARS-CoV-2 wouldn't mutate rapidly due to its self-repair mechanism. However, numerous variants emerged globally, including Alpha, Beta, Delta, and Omicron. Herman's team, armed with tARC-seq, determined mutation rates higher than expected, explaining variant emergence.
They identified mutation hotspots, notably in the spike protein RNA, crucial for viral entry and vaccine composition. tARC-seq unveiled template switching, where the virus jumps between RNA templates during replication, leading to complex mutations and increased variability.Â
Herman noted tARC-seq's ability to monitor mutations in lab cultures and clinical samples, essential for understanding viral evolution. This technology provides a snapshot of mutation dynamics, aiding in pandemic surveillance and vaccine development.
2024-04-23T09:46:21Z dg43tfdfdgfd
