Several studies have evaluated the association between FTO polymorphisms (rs9939609 and rs1558902) and obesity in different populations, including Turkish population (NCT04205318), Indonesian obesity women (NCT04740528), as well as weight loss in overweight carriers induced by calorie restriction (NCT02940197), and intermittent or moderate continuous high intensity training programs (NCT03568773). This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.