The genotypes associated with these Fto SNPs affect the expression level of Fto (Berulava and Horsthemke, 2010; Pahl et al, 2023; Stratigopoulos et al, 2016; Zhang et al, 2023) and neighboring genes such as Rpgrip1l, Irx3, and Irx5, which are related to obesity (Smemo et al, 2014). This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.