ReviewMicrobiology and molecular biology reviews : MMBR2021
The Baltimore Classification of Viruses 50 Years Later: How Does It Stand in the Light of Virus Evolution?
Review in Microbiology and molecular biology reviews : MMBR, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 64 papers.
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Who cites it
64 citing papers in PubMed.
- Why did some viruses evolve to be giants while others did not?Proceedings of the National Academy of Sciences of the United States of America · 2026Article
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- Molecular Insights into High-Pathogenicity RNA Viruses.Viruses · 2026Review
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- A novel transformer model of protein domains for viral taxonomy classification.Bioinformatics (Oxford, England) · 2026Article
- Viral infections alter the human salivary volatilome.mSphere · 2026Article
- Lead Optimization of Xanthone Derivatives as Hepatitis B Virus cccDNA Reducers: Design, Synthesis, and Bioevaluation.ACS medicinal chemistry letters · 2026Article
- The chicken gut virome: spatial structuring and extensive diversity of 19,778 viral populations.mSystems · 2026Article
- Biological Activity of Stilbenoids Against Fungal, Parasitic, and Viral Pathogens.Molecules (Basel, Switzerland) · 2026Review
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- Meta-virus resource (MetaVR): expanding the frontiers of viral diversity with 24 million uncultivated virus genomes.Nucleic acids research · 2026Article
- Roles of Reactive Oxygen Species in Relationships Between Viral Infections and Alzheimer's Disease and Related Dementia.Antioxidants (Basel, Switzerland) · 2026Review
- Spatial and depth structuring predominate over temporal variation in Mediterranean climate grassland soil viral communities.ISME communications · 2026Article
- Universal and quantitative detection of double-stranded RNAs as a signature of pan-virus infections using a luciferase-based biosensor.Journal of biological engineering · 2025Article
- The p48 isoform of the PA2G4/EBP1/ITAF45 oncoprotein is required for the encephalomyocarditis virus IRES-driven translation initiation.Nucleic acids research · 2025Article
- Antiviral nanomedicine: Advantages, mechanisms and advanced therapies.Bioactive materials · 2025Review
- Transient receptor potential channels in viral infectious diseases: Biological characteristics and regulatory mechanisms.Journal of advanced research · 2025Review
- Membrane-Targeting Antivirals.International journal of molecular sciences · 2025Review
- CRISPR/Cas13-Based Anti-RNA Viral Approaches.Genes · 2025Review
4 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Fifty years ago, David Baltimore published a brief conceptual paper delineating the classification of viruses by the routes of genome expression. The six "Baltimore classes" of viruses, with a subsequently added 7th class, became the conceptual framework for the development of virology during the next five decades. During this time, it became clear that the Baltimore classes, with relatively minor additions, indeed cover the diversity of virus genome expression schemes that also define the replication cycles. Here, we examine the status of the Baltimore classes 50 years after their advent and explore their links with the global ecology and biology of the respective viruses. We discuss an extension of the Baltimore scheme and why many logically admissible expression-replication schemes do not appear to be realized in nature. Recent phylogenomic analyses allow tracing the complex connections between the Baltimore classes and the monophyletic realms of viruses. The five classes of RNA viruses and reverse-transcribing viruses share an origin, whereas both the single-stranded DNA viruses and double-stranded DNA (dsDNA) viruses evolved on multiple independent occasions. Most of the Baltimore classes of viruses probably emerged during the earliest era of life evolution, at the stage of the primordial pool of diverse replicators, and before the advent of modern-like cells with large dsDNA genomes. The Baltimore classes remain an integral part of the conceptual foundation of biology, providing the essential structure for the logical space of information transfer processes, which is nontrivially connected with the routes of evolution of viruses and other replicators.
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