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Exploring Diversity of COVID‑19 Based on Substitution Distance
1Institute of Statistical Science, Academia Sinica, Nankang, Taipei, Taiwan.
Infection and Drug Resistance
|November 5, 2020
Summary
The study reveals that the nucleotide substitution distance of SARS-CoV-2 sequences correlates with the virus
Area of Science:
- Virology and Molecular Epidemiology
- Genomic Analysis of Viral Evolution
Background:
- Over 10 million COVID-19 infections globally highlight the pandemic's scale.
- SARS-CoV-2, the virus causing COVID-19, exhibits higher transmissibility than SARS-CoV-1.
- The precise origin of COVID-19 remains a subject of scientific inquiry, though SARS-CoV-2 sequences trace to late 2019.
Purpose of the Study:
- To investigate the diversity of SARS-CoV-2 nucleotide sequences.
- To infer the origin of COVID-19 by analyzing sequence diversity across different geographical regions.
Main Methods:
- Calculated nucleotide substitution distances for SARS-CoV-2 samples from China, Europe, and the USA using various substitution models.
- Assessed sequence diversity as a proxy for viral evolution over time.
- Employed ANOVA testing to determine statistical significance of observed differences.
Main Results:
- Significant differences in SARS-CoV-2 nucleotide substitution distances were observed among China, Europe, and the USA (p < 2.2e-16).
- Samples from China exhibited the lowest sequence diversity, followed by Europe, and then the USA.
- These findings align with the established timeline of COVID-19 transmission, originating in China and spreading to Europe and the USA.
Conclusions:
- Nucleotide substitution distance is a reliable indicator of SARS-CoV-2 transmission order.
- This metric can be effectively utilized to infer the geographical origin of COVID-19 outbreaks.
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