Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Enhancer evolution in mammals

Widespread changes in regulatory genomic regions have underpinned mammalian evolution, but our knowledge about these regions is still incomplete. Paul Flicek, Duncan Odom and colleagues have now contributed to a better understanding of how the noncoding portions of mammalian genomes have been reshaped over the last 180 million years (Cell 160, 554–566, 2015). They characterized active promoters and enhancers in liver samples from 20 mammalian species—from Tasmanian devil to human—by examining the genome-wide enrichment profiles of H3K4me3 and H3K27ac, two histone modifications associated with transcriptional activity. Their analyses suggest that rapid enhancer evolution and high promoter conservation are fundamental traits of mammalian genomes. Intriguingly, they find that the majority of newly evolved enhancers originated via functional exaptation of ancestral DNA and not through clade-specific expansions of repeat elements. Their data also indicate that this class of putative enhancers is often associated with genes under positive selection. Future studies could extend these analyses to distinct subtypes of enhancers, to different developmental stages and to additional organs, taking into account tissue and cell heterogeneity. Moreover, as our understanding of chromatin biology deepens, it will be interesting to have a closer look at the evolution of other regulatory elements.


Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Faial, T. Enhancer evolution in mammals. Nat Genet 47, 198 (2015).

Download citation


Quick links