GPR151 and obesity due to melanocortin 4 receptor deficiency: Recently, a rare nonsynonymous, presumed inactivating, mutation (p.Arg95Ter) in the gene encoding the orphan G-protein coupled receptor 151 (GPR151), a Gαo1-linked GPCR, was associated with lower odds ratio for T2D, obesity and coronary artery disease6 and with reduced body-mass index (BMI)6–8, although another recent study found no significant associations between putative loss-of-function (LOF) GPR151 variants and BMI, T2D, or other metabolic traits9.