Melanocortin Receptor 1 (MC1R) belongs to a five-member receptor family known as the melanocortin receptors. The melanocortin receptors are members of the 7-transmembrane domain, G protein-coupled receptor (GPCR) superfamily.The receptors ligands, the melanocortins, are a group of structurally derived peptides consisting of α-, β- and γ-melanocyte stimulating hormone (α, β, γ-MSH) and the adrenocorticotropic hormone (ACTH) all of which are derived from the post-translational processing of a common precursor peptide, proopiomelanocortin (POMC)