Genome-wide association (GWA) studies have so far identified a large number of single nucleotide polymorphisms (SNPs) in different genes associated with susceptibility to obesity and metabolic diseases, including genetic variants in BDNF, FTO, GCK, GCKR, KCNQ1, MC4R, PROX1, UBE2E2, and so on (13–16). This evidence concerns the gene KCNQ1 and obesity due to melanocortin 4 receptor deficiency.