Although the LEP promoter polymorphism G‐2548A (rs7799039) has been studied intensively (De Silva et al., 1999; Duarte, Colagiuri, Palu, Wang, & Wilcken, 2003; Furusawa et al., 2011; Paracchini, Pedotti, & Taioli, 2005; Wang et al., 2006), the results for the associated single‐nucleotide polymorphism (SNP) and their alleles, which may indicate the roles of genetic and environmental factors in obesity, have been controversial. Here, LEP is linked to obesity due to melanocortin 4 receptor deficiency.