Eighty children with normal weight, overweight, or obesity were analyzed for serum vitamin D, C-reactive protein, leukocytes, adiponectin, monocyte chemoattractant protein-1, myeloperoxidase, interferon-inducible T-cell alpha chemoattractant (I-TAC/CXCL11), superoxide dismutase-1, fasting lipid and glucose levels, ultrasound-measured abdominal fat thickness, waist circumference, body mass index and blood pressure. The gene discussed is CXCL11; the disease is obesity due to melanocortin 4 receptor deficiency.