de Luis et al. (55) investigated the influence of the variation Ala54Thr in the intestinal fatty acid-binding protein 2 gene (FABP2) on metabolic response secondary to the intake of a high-protein/low-carbohydrate (HP) vs. standard hypocaloric diet in subjects with obesity during 9 months. This evidence concerns the gene FABP2 and obesity due to melanocortin 4 receptor deficiency.