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ICTV Virus Taxonomy Profile: Circoviridae
Mya Breitbart1, Eric Delwart2, Karyna Rosario1
1College of Marine Science, University of South Florida, 140 7th Avenue South, Saint Petersburg, FL 33701, USA.
The Journal of General Virology
|August 9, 2017
Summary
The Circoviridae family includes the smallest animal viruses, featuring circular, single-stranded DNA genomes. This report details their taxonomy, classifying them into Circovirus and Cyclovirus genera based on replication origins and intergenic regions.
Area of Science:
- Virology
- Molecular Biology
- Taxonomy
Background:
- The family Circoviridae encompasses viruses with small, circular, single-stranded DNA (ssDNA) genomes.
- These viruses include some of the smallest known animal viruses.
- Current classification distinguishes two genera: Circovirus and Cyclovirus.
Purpose of the Study:
- To summarize the International Committee on Taxonomy of Viruses (ICTV) report on Circoviridae taxonomy.
- To outline the criteria for classifying viruses within the Circoviridae family.
- To provide an accessible overview of the current taxonomic framework for Circoviridae.
Main Methods:
- Review and summarization of the official ICTV report on Circoviridae.
- Analysis of taxonomic criteria including genome structure and replication origins.
- Identification of species demarcation thresholds based on nucleotide sequence identity.
Main Results:
- Circoviridae viruses possess small, circular, ssDNA genomes.
- Two genera, Circovirus and Cyclovirus, are defined by the position of the origin of replication and intergenic region length.
- A 80% genome-wide nucleotide sequence identity threshold is used for species demarcation within each genus.
Conclusions:
- The ICTV provides a standardized taxonomic framework for the Circoviridae family.
- Distinct characteristics differentiate the Circovirus and Cyclovirus genera.
- The established species demarcation threshold ensures consistent classification of Circoviridae.
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