When divided into participants suffering from overweight, obesity, diabetes, hyperlipidemia and/or hypertension (n = 143) or healthy (n = 220), the median values of zonulin were 56.8 (45.8–68.6) ng/mL vs. 53.0 (44.2–61.9) ng/mL (p = 0.008). The gene discussed is HP; the disease is obesity due to melanocortin 4 receptor deficiency.