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One Year of SARS-CoV-2: How Much Has the Virus Changed?
Santiago Vilar1, Daniel G Isom1,2,3
1Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
Biology
|February 3, 2021
Summary
SARS-CoV-2 proteins mutate at varying rates, with most showing low variability. Analysis of nearly 300,000 sequences revealed distinct mutation periods and geographical differences, offering insights into viral evolution.
Area of Science:
- Virology
- Genomics
- Molecular Biology
Background:
- The COVID-19 pandemic, caused by SARS-CoV-2, has led to a global health and economic crisis.
- Extensive sharing of viral genome sequences via GISAID aids in tracking viral evolution.
Purpose of the Study:
- To analyze the mutation rates across the entire SARS-CoV-2 proteome using publicly available sequence data.
- To identify temporal and geographical patterns in viral mutations and assess site-specific mutational tolerance.
Main Methods:
- Analysis of approximately 290,000 full SARS-CoV-2 proteome sequences from GISAID.
- Temporal and geographical analyses of mutation rates.
- Structure-based molecular analysis of protein structures.
Main Results:
- Most SARS-CoV-2 proteins exhibit low mutational variability, but mutation rates differ significantly across the proteome.
- Identified known mutations (e.g., D614G in Spike) and novel mutations (e.g., A222V in Spike).
- Observed two distinct periods of proteome mutation rates (Dec 2019-Jul 2020 and Aug-Dec 2020), with geographical variations noted, particularly in Europe during late 2020.
Conclusions:
- SARS-CoV-2 proteome mutation rates are not uniform and vary over time and by geography.
- Structure-based analysis provides insights into the mutational tolerance of specific viral protein sites.
- Understanding these mutation dynamics is crucial for ongoing efforts to control the pandemic.
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