Numerous genes annotated to these putative enhancer regions e.g. CACNA1D, GLIS3, GRB10, HDAC9, HNF1B, INSIG2, PAX6, PDK4, SLC2A2 and TXNIP are known to be involved in T2D and islet function27,29–32. This evidence concerns the gene PDK4 and type 2 diabetes mellitus.