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Updated: Jul 16, 2026
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Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Evidence for a high frequency of simultaneous double-nucleotide substitutions
1Institute of Molecular Biology and Biotechnology (IMBB)-FORTH, Vassilika Vouton, 711 10 Iraklio, Crete, Greece.
Science (New York, N.Y.)
|February 26, 2000
Summary
Simultaneous double-nucleotide substitutions, where multiple adjacent DNA bases change at once, occur more frequently than previously assumed. This study estimates their rate at approximately 0.1 per site per billion years.
Area of Science:
- Genetics
- Molecular Biology
- Evolutionary Biology
Background:
- Point mutations typically involve single nucleotide changes.
- Mechanisms of mutation do not inherently exclude simultaneous changes in adjacent nucleotides.
Purpose of the Study:
- To estimate the frequency of simultaneous double-nucleotide substitutions.
- To investigate the occurrence of multiple adjacent nucleotide changes in a single mutational event.
Main Methods:
- Analysis of codon switches (TCN to AGY) for conserved serine residues in proteins.
- Identification of double-nucleotide substitutions in primate noncoding DNA sequences.
Main Results:
- Two independent methods yielded similar high estimates for doublet substitution rates.
- The estimated rate of double-nucleotide substitutions is approximately 0.1 per site per billion years.
Conclusions:
- Simultaneous double-nucleotide substitutions are a significant factor in genetic mutation.
- The findings challenge the exclusive focus on single-nucleotide changes in mutation studies.
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