epigenomic annotations (e.g., from ENCODE or NIH Roadmap) indicating that the intronic locus in FTO contained an enhancer for IRX3/IRX5, the phenotypic effects of which were subsequently confirmed through mouse and patient tissue samples (Claussnitzer et al., 2015). Understanding the function of associated loci can be a powerful tool to understand which variants to prioritize for later experiments, and also to elucidate biological mechanisms of action.
