CACNA1D and type 2 diabetes mellitus: 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.