Understanding how gene expression is regulated to direct cellular differentiation and cooperation poses a fundamental challenge for biologists. The central dogma of DNA to RNA to protein does not capture the full picture. Most of the human variation identified by genome-wide association studies (GWAS) is found in noncoding regions, including introns, promoters, or enhancers. This suggests that changes to protein coding regions do not fully explain the impact of genetic polymorphism on human health. Epigenomics spans the gaps in the central dogma, revealing a layer of biological control “above” the genome sequence.