Dataset Information

SARS-CoV-2 Mutant Spectra at Different Depth Levels Reveal an Overwhelming Abundance of Low Frequency Mutations.

ABSTRACT: Populations of RNA viruses are composed of complex and dynamic mixtures of variant genomes that are termed mutant spectra or mutant clouds. This applies also to SARS-CoV-2, and mutations that are detected at low frequency in an infected individual can be dominant (represented in the consensus sequence) in subsequent variants of interest or variants of concern. Here we briefly review the main conclusions of our work on mutant spectrum characterization of hepatitis C virus (HCV) and SARS-CoV-2 at the nucleotide and amino acid levels and address the following two new questions derived from previous results: (i) how is the SARS-CoV-2 mutant and deletion spectrum composition in diagnostic samples, when examined at progressively lower cut-off mutant frequency values in ultra-deep sequencing; (ii) how the frequency distribution of minority amino acid substitutions in SARS-CoV-2 compares with that of HCV sampled also from infected patients. The main conclusions are the following: (i) the number of different mutations found at low frequency in SARS-CoV-2 mutant spectra increases dramatically (50- to 100-fold) as the cut-off frequency for mutation detection is lowered from 0.5% to 0.1%, and (ii) that, contrary to HCV, SARS-CoV-2 mutant spectra exhibit a deficit of intermediate frequency amino acid substitutions. The possible origin and implications of mutant spectrum differences among RNA viruses are discussed.

SUBMITTER: Martinez-Gonzalez B

PROVIDER: S-EPMC9227345 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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SARS-CoV-2 Mutant Spectra at Different Depth Levels Reveal an Overwhelming Abundance of Low Frequency Mutations.

Martínez-González Brenda B Soria María Eugenia ME Vázquez-Sirvent Lucía L Ferrer-Orta Cristina C Lobo-Vega Rebeca R Mínguez Pablo P de la Fuente Lorena L Llorens Carlos C Soriano Beatriz B Ramos-Ruíz Ricardo R Cortón Marta M López-Rodríguez Rosario R García-Crespo Carlos C Somovilla Pilar P Durán-Pastor Antoni A Gallego Isabel I de Ávila Ana Isabel AI Delgado Soledad S Morán Federico F López-Galíndez Cecilio C Gómez Jordi J Enjuanes Luis L Salar-Vidal Llanos L Esteban-Muñoz Mario M Esteban Jaime J Fernández-Roblas Ricardo R Gadea Ignacio I Ayuso Carmen C Ruíz-Hornillos Javier J Verdaguer Nuria N Domingo Esteban E Perales Celia C

Pathogens (Basel, Switzerland) 20220608 6

Populations of RNA viruses are composed of complex and dynamic mixtures of variant genomes that are termed mutant spectra or mutant clouds. This applies also to SARS-CoV-2, and mutations that are detected at low frequency in an infected individual can be dominant (represented in the consensus sequence) in subsequent variants of interest or variants of concern. Here we briefly review the main conclusions of our work on mutant spectrum characterization of hepatitis C virus (HCV) and SARS-CoV-2 at ...[more]

PMID: 35745516

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Dataset Information

SARS-CoV-2 Mutant Spectra at Different Depth Levels Reveal an Overwhelming Abundance of Low Frequency Mutations.

Publications

SARS-CoV-2 Mutant Spectra at Different Depth Levels Reveal an Overwhelming Abundance of Low Frequency Mutations.

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