Recent studies have demonstrated a clear potential for a precision medicine approach based on glycaemic response, with the TRIMASTER crossover trial establishing a greater efficacy of SGLT2i compared with DPP4 inhibitors (DPP4i) in those with better renal function, and a greater efficacy of thiazolidinedione therapy compared with DPP4i in those with obesity (BMI > 30 kg/m2) compared to those without obesity [5]. The gene discussed is DPP4; the disease is obesity disorder.