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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Short indels are subject to insertion-biased gene conversion
Evgeny V Leushkin1, Georgii A Bazykin
1Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Leninskye Gory 1-73, Moscow, 119992, Russia; Institute for Information Transmission Problems of the Russian Academy of Sciences (Kharkevich Institute), Bolshoi Karetny pereulok, 19, Moscow, 127994, Russia. leushkin@gmail.com.
Evolution; International Journal of Organic Evolution
|September 17, 2013
Summary
Gene conversion, a DNA repair process, favors insertions over deletions in high-recombination regions. This insertion bias, particularly for short indels, significantly impacts DNA evolution across species.
Area of Science:
- Genetics
- Molecular Biology
- Evolutionary Biology
Background:
- Gene conversion, a process repairing DNA mismatches, often results in GC-biased nucleotide substitutions.
- Previous studies established GC-bias in gene conversion for single nucleotide substitutions.
Purpose of the Study:
- To investigate the relationship between recombination rates and the fixation of insertions and deletions (indels).
- To determine the underlying mechanisms driving observed trends in indel fixation ratios.
Main Methods:
- Analysis of whole-genome data on indel polymorphism and divergence in Drosophila melanogaster.
- Comparative analysis across Drosophila melanogaster, Homo sapiens, and Saccharomyces cerevisiae.
Main Results:
- A positive correlation was found between recombination rate and the insertion/deletion fixation ratio for short noncoding indels.
- High recombination rates increase indel insertion fixation and decrease deletion fixation.
- The insertion bias is strongest for single-nucleotide indels and diminishes with increasing indel length.
Conclusions:
- Insertion-biased gene conversion is the most probable cause for the excess of fixed insertions over deletions in high-recombination regions.
- This bias significantly influences the evolution of DNA segments, particularly short indels.
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