Instead Grb7 may positively influence fetal kidney growth, acting antagonistically to Grb10. In contrast, we have provided evidence that Grb7 can contribute to the regulation of whole-body glucose handling along with Grb10 and Grb14. This places all three signalling adaptor proteins in the frame as important regulators of energy homeostasis and potential therapeutic targets for major metabolic disorders including obesity, type 2 diabetes and NAFLD. This evidence concerns the gene GRB7 and obesity due to melanocortin 4 receptor deficiency.