Clinically, endocrinological diseases as obesity, type 2 diabetes mellitus, and Cushing’s syndrome are all characterized by chronic elevation of circulating FFAs and a substantial depression of the somatotropic function has been documented, thus supporting the hypothesis that FFAs play a prominent role in the pathogenesis of GH secretion alterations that are characteristic of these diseases [197,198,199,200]. The gene discussed is GH1; the disease is obesity due to melanocortin 4 receptor deficiency.