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Alastrim smallpox variola minor virus genome DNA sequences
S N Shchelkunov1, A V Totmenin, V N Loparev
1Department of Molecular Biology of Genomes, State Research Center of Virology and Biotechnology (Vector), Koltsovo, Novosibirsk Region, 633159, Russia. snshchel@vector.nsk.su
Virology
|January 20, 2000
Summary
Alastrim variola minor virus, a mild smallpox strain, was sequenced. Its genome shows high similarity to variola major virus, with unique DNA segments.
Area of Science:
- Virology
- Genomics
- Molecular Biology
Background:
- Alastrim variola minor virus, responsible for mild smallpox, was identified in the late 19th century.
- This study focuses on the Garcia-1966 laboratory reference strain from a 1966 Brazilian outbreak.
Purpose of the Study:
- To determine the complete genome sequence of the alastrim virus Garcia-1966 strain.
- To compare the alastrim virus genome with variola major and other orthopoxviruses.
Main Methods:
- DNA sequencing of the alastrim virus Garcia-1966 genome.
- Bioinformatic analysis to identify open reading frames and compare protein sequences.
- Comparative genomic analysis with variola major and other orthopoxviruses.
Main Results:
- The genome sequence of alastrim virus Garcia-1966 was determined, revealing 206 potential protein-coding regions.
- Alastrim viral proteins showed high identity (>95%) to variola major virus proteins, with about one-third being 100% identical.
- Alastrim virus DNA contains unique terminal segments not found in variola major virus, with one segment showing homology to other orthopoxviruses.
Conclusions:
- Alastrim virus is genetically closely related to variola major virus.
- Distinct DNA segments in the alastrim virus genome may contribute to its distinct characteristics.
- Genomic insights into alastrim virus can aid in understanding orthopoxvirus evolution and pathogenesis.
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