GRK5 and obesity due to melanocortin 4 receptor deficiency: Interestingly this gene has protein interactions with many known obesity genes (e.g., MC4R, POMC, ADRB2, ADCY9 and BDNF) and also many known Type 2 diabetes associated genes (INS-IGF2, GRK5, ADCY5) within the subnetwork, supporting its critical role in mediating the Type 2 diabetes-obesity interaction in the function module.