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Updated: Oct 4, 2025
05:45
Validating Whole Genome Nanopore Sequencing, using Usutu Virus as an Example
Published on: March 11, 2020
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Human SARS-CoV-2 has evolved to increase U content and reduce genome size
Yong Wang1, Xin-Yu Chen1, Liu Yang1
1School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.
International Journal of Biological Macromolecules
|February 12, 2022
Summary
The SARS-CoV-2 virus is evolving towards higher U-content and smaller genomes, making it more infectious but less virulent. This genome evolution trend may help trace the virus's origin.
Area of Science:
- Virology
- Genomics
- Molecular Biology
Background:
- Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have caused significant global health issues.
- Over two years, SARS-CoV-2 has evolved into numerous distinct lineages, complicating transmission control.
- Understanding viral genome evolution is crucial for predicting future challenges in managing the pandemic.
Purpose of the Study:
- To analyze the evolutionary trends of SARS-CoV-2 genome.
- To investigate nucleotide, amino acid, and codon variations in SARS-CoV-2.
- To correlate genome evolution with viral characteristics like infectivity and virulence.
Main Methods:
- Conducted monthly surveys and in-depth analysis of 311,260 SARS-CoV-2 samples collected until January 2022.
- Examined variations in nucleotide, amino acid, and codon composition.
- Compared mutation patterns across different SARS-CoV-2 lineages.
Main Results:
- SARS-CoV-2 evolution shows a trend towards increased U-content and reduced genome size.
- Mutations from C, G, and A to U contribute to the rising U-content.
- Current SARS-CoV-2 variants are less virulent but more infectious, with Delta and Omicron exhibiting high mutability.
Conclusions:
- The observed genome evolution trend suggests SARS-CoV-2 is becoming more efficient at replication.
- Increased infectiousness and decreased virulence are key characteristics of current strains.
- The trend of increasing U-content and decreasing genome size may aid in tracing the ancestral origins of SARS-CoV-2.
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