The common risk factors for PTDM include obesity, sedentary lifestyle, other metabolic syndromes associated with obesity, certain viral infections (e.g., hepatitis C virus and cytomegalovirus), and the use of drugs with diabetogenic effects administered with post-transplantation therapy, including corticosteroids and immunosuppressive agents (e.g., tacrolimus, cyclosporine, and mammalian target of rapamycin inhibitors (mTORis)) [13]. The gene discussed is MTOR; the disease is obesity due to melanocortin 4 receptor deficiency.