Genetic Heterogeneity of Variation in Skin/Hair/Eye Pigmentation Multiple genes influence normal human skin, hair, and/or eye pigmentation. Pigmentation phenotypes influenced by variation in the OCA2 gene are termed SHEP1. The SHEP2 association (266300) is determined by variation at the MC1R locus (155555) and describes a phenotype predominantly characterized by red hair and fair skin. SHEP3 (601800) encompasses pigment variation influenced by the TYR gene (606933); SHEP4 (113750), that influenced by the SLC24A5 gene (609802). Variation in the SLC45A2 (606202) and SLC24A4 (609840) genes result in the phenotypic associations SHEP5 (227240) and SHEP6 (210750), respectively. Sequence variation thought to affect expression of KITLG (184745) results in the SHEP7 (611664) phenotypic association. SHEP8 (611724) is associated with variation in the IRF4 gene (601900). Polymorphism in the 3-prime untranslated region of the ASIP gene (600201) influences the SHEP9 association (611742). The SHEP10 association (612267) comprises variation in the TPCN2 gene (612163), and SHEP11 (612271) is associated with polymorphism near the TYRP1 gene (115501). [from OMIM]