Figure 7. Lack of correlation between expression level and SNP frequency in S. cerevisiae.

(A) Median expression for intergenic regions and transcripts, as a function of distance from telomeres. (B) Boxplots of SNP frequencies for intergenic regions, as a function of median expression level. (C) Boxplots of SNP frequencies in fourfold-degenerate synonymous positions of genes, as a function of median expression level. Wilcoxon–Mann–Whitney p-values for each expression level, comparing SNP frequencies against the genome-wide distribution, are indicated within each boxplot.