To establish diagnosis of NAFLD and to screen children for possible obesity-related metabolic complications, triglycerides, cholesterol, basal and/or stimulated glucose and/or insulin, and liver enzymes like aspartate aminotransferase (AST), alanine-aminotransferase (ALT) and gamma glutamyltransferase (gammaGT) are measured [11, 6]. The gene discussed is GPT; the disease is obesity due to melanocortin 4 receptor deficiency.