CARTPT and obesity due to melanocortin 4 receptor deficiency: We compared ARC gene expression in 8-week-old and 36-week-old Crtc1−/− and WT males (Table 1 and Fig. 2a–h), as well as the relative expression of four anorexigenic genes (LepRb, Cart, Nor1, and Glp-r1), three orexigenic genes (AgRP, Npy, and Npy-y1) and the fat-mass-related and obesity-related gene (Fto).