Recent evidence for pervasive adaptation targeting gene expression attributable to population size change

Abstract

Addressing the current interest in the role of selection in the evolution of gene regulation, the study by Fraser et al. (1) proposes a test based on coherent effects of cis and trans expression quantitative trait loci to detect lineage-specific selection on gene expression using genome-wide data from Saccharomyces cerevisiae. Based on both this test statistic (a modification of the standard McDonald–Kreitman 2 × 2 contingency table) and population genetic analyses, the authors claim evidence for widespread selective sweeps—concluding that S. cerevisiae is evolving primarily through adaptive modification of expression levels.