Viruses: Genomes and Genomics


The virus genome is the nucleic acid component of a virus which encodes the genetic information. The type of nucleic acid inside the virus particle (ribonucleic acid (RNA)/deoxyribonucleic acid (DNA), single/double strands) and whether or not the virus uses reverse transcription during replication are fundamental classifications criteria dividing viruses into seven classes. Even within these classes there is great range of genome sizes and organizations, making viruses highly diverse entities. The usually small size of virus genomes makes them particularly amenable to sequencing, and as high‐throughput methods become more commonplace, virus genomics is becoming increasingly prominent. It promises to provide a wealth of new information on the function of virus proteins and nucleic acid structures, virus evolution and how viruses cause disease, which will underpin the development and monitoring of new therapeutic approaches.

Keywords: composition; structure; virus genomes; genomics; evolution

Figure 1.

Comparison of genome sizes. CV, Circovirus; MV, Mimovirus; E. coli, Escherichia coli.

Figure 2.

Comparison of frequency of genome types based on species number. ds, double‐stranded; ss, single‐stranded; RT, reverse transcriptase‐using.



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Further Reading

Cann AJ (2005) Principles of Molecular Virology. 4th edn. Amsterdam: Academic Press.

Flint SJ (ed.) (2004) Principles in Virology: Molecular Biology, Pathogenesis and Control of Animal Viruses. 2nd edn. Washington: ASM Press.

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Williams, Çiğdem H, and Stanway, Glyn(Mar 2009) Viruses: Genomes and Genomics. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0001092.pub2]