Recently, many single nucleotide polymorphisms (SNPs) were identified by genome-wide association studies (GWASs) in adults and children with respect to the pathogenesis of obesity, including FTO, TMEM18, GNPDA2, INSIG2, MC4R, NEGR1, 1q25, BDNF and KCTD15[7]. Here, MC4R is linked to obesity due to melanocortin 4 receptor deficiency.