The role of FTO in maintenance and regulation of energy homeostasis and food intake has been demonstrated in animal models [317] and through GWAS relationships to insulin resistance and obesity [318,319], Alzheimer’s disease [320], cardiovascular disease [321] and renal failure [322], as well as breast and colorectal cancer [323,324] have been established. This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.