INS and obesity due to melanocortin 4 receptor deficiency: Significantly increased levels of leptin (68.5 ± 0.35 ng/mL versus 66.73 ± 0.42 ng/mL; p = 0.012) and insulin (98.03 ± 0.54 μIU/mL versus 95.51 ± 0.47 μIU/mL; p = 0.008) suggested a strong resistance to these hormones, typical of monogenic obesity types.