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Updated: Jul 11, 2026
11:36
A Protocol for Functional Assessment of Whole-Protein Saturation Mutagenesis Libraries Utilizing High-Throughput Sequencing
Published on: July 3, 2016
A maximum-likelihood approach to fitting equilibrium models of microsatellite evolution.
R M Sibly1, J C Whittaker, M Talbot
1School of Animal and Microbial Sciences, Department of Applied Statistics, University of Reading, Reading, England. r.m.sibly@reading.ac.uk
Molecular Biology and Evolution
|March 7, 2001
Summary
This study introduces new Markov chain models for microsatellite evolution, revealing that slippage rates increase with microsatellite length but are negligible for very short sequences. These findings offer insights into polymerase slippage mechanisms.
Area of Science:
- Genetics
- Computational Biology
- Evolutionary Biology
Background:
- Microsatellites are repetitive DNA sequences prone to mutations via polymerase slippage.
- Previous models of microsatellite evolution often assumed constant slippage rates, irrespective of microsatellite length.
Purpose of the Study:
- To develop and apply novel Markov chain models for microsatellite evolution.
- To investigate the relationship between microsatellite length and polymerase slippage rate.
- To enable robust statistical comparisons between different evolutionary models.
Main Methods:
- Development of hierarchical Markov chain models, including constant-slippage-rate and linear models.
- Application of maximum likelihood estimation for fitting models to data.
- Statistical comparison of model performance.
Main Results:
- Statistically confirmed that slippage rate increases with microsatellite length for dinucleotide microsatellites in humans, mice, and fruit flies.
- Indicated that polymerase slippage is negligible in very short microsatellites (1-4 repeats).
Conclusions:
- The developed modeling approach allows for statistically sound comparisons of microsatellite evolution models.
- Polymerase slippage is length-dependent, with minimal activity in short microsatellites.
- These findings have significant implications for understanding the fundamental mechanisms of DNA replication and microsatellite instability.
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