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How long ago did smallpox virus emerge?
1Department of Poxvirus Genomic Research, State Research Center of Virology and Biotechnology VECTOR, Koltsovo, Novosibirsk oblast, Russia. snshchel@vector.nsc.ru
Archives of Virology
|November 3, 2009
Summary
Estimating the evolutionary timeline for DNA viruses like smallpox (variola) virus (VARV) is challenging due to their slow mutation rate. This study reviews dating methods and supports a recent origin for VARV.
Area of Science:
- Virology
- Molecular Evolution
- Paleogenomics
Background:
- Estimating molecular evolution time parameters for DNA viruses is complex due to their low mutation rates, unlike RNA viruses or vertebrates.
- Previous genomic studies of smallpox (variola) virus (VARV) isolates revealed phylogenetic relationships among geographic variants.
- Contradictory data exist regarding the origin time of VARV, based on archival outbreak data and phylogenetic analyses.
Purpose of the Study:
- To discuss various approaches for dating the molecular evolution of VARV.
- To present arguments supporting a historically recent origin for VARV.
Main Methods:
- Phylogenetic analysis of poxvirus genomes.
- Analysis of archival data on smallpox outbreaks.
Main Results:
- Genomic studies have elucidated phylogenetic relationships among VARV geographic variants.
- Discrepancies in origin dating suggest challenges in VARV evolutionary timeline estimation.
- Arguments favor a recent origin for VARV.
Conclusions:
- Dating the molecular evolution of DNA viruses like VARV presents unique challenges.
- A comprehensive review of dating methodologies is crucial for understanding VARV's evolutionary history.
- Evidence suggests VARV likely has a historically recent origin.
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