Studies on associations in females have been reported for the estrogen receptor (ESR1 or ESR2) with MetS or its components, particularly with obesity and dyslipidemia [6]; these associations might be explained by single nucleotide polymorphisms (SNPs) in the ESR1 gene, as reported by some studies [7,8]. The gene discussed is ESR1; the disease is obesity due to melanocortin 4 receptor deficiency.