• Corpus ID: 2879007

Horizontal gene transfer may explain variation in {\theta}s

@article{Maddamsetti2012HorizontalGT,
  title={Horizontal gene transfer may explain variation in \{\theta\}s},
  author={Rohan Maddamsetti and Philip J. Hatcher and St{\'e}phane Cruveiller and Claudine M'edigue and Jeffrey E. Barrick and Richard E. Lenski},
  journal={arXiv: Populations and Evolution},
  year={2012}
}
Martincorena et al. estimated synonymous diversity ({\theta}s = 2N{\mu}) across 2,930 orthologous gene alignments from 34 Escherichia coli genomes, and found substantial variation among genes in the density of synonymous polymorphisms. They argue that this pattern reflects variation in the mutation rate per nucleotide ({\mu}) among genes. However, the effective population size (N) is not necessarily constant across the genome. In particular, different genes may have different histories of… 

Figures from this paper

Response to Horizontal gene transfer may explain variation in theta_s
TLDR
It is shown that HGT was carefully accounted for in this study by multiple independent phylogenetic and population genetic approaches, and there is no new evidence of HGT affecting results, so caution must be exercised when comparing mutations from repair deficient strains to data from wild-type strains, as these conditions are dominated by different mutational processes.
Links between Transcription, Environmental Adaptation and Gene Variability in Escherichia coli: Correlations between Gene Expression and Gene Variability Reflect Growth Efficiencies.
TLDR
It is suggested that gene expression under stressful conditions may be mutagenic and thus leads to a variability in mutation rate among genes in the genome which contributes to the pattern of protein evolution.

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