GPCRs that have received recent attention in the field of diabetes therapeutics include the incretin receptors (GLP1R, GIPR), GPR119, FFAR1 (GPR40), FFAR4 (GPR120) and the bile acid receptor GPBAR1 (TGR5) (for examples, see [2, 3, 5–7]) (see text box). This evidence concerns the gene FFAR4 and diabetes mellitus.