On the other hand, the significance of m6A-RNA methylation in adipogenesis has recently been reported, as fat mass and obesity-associated protein (FTO), which was previously identified by human genome-wide association studies (GWAS) with strong association with obesity (11), has been demonstrated to be a demethylase of m6A of RNA (12) and promotes adipogenesis in vitro and development of obesity in vivo (13, –, 15). This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.