White Sponge Nevus, also known as hereditary mucosal leukokeratosis, is related to leukoplakia and familial woolly hair syndrome. An important gene associated with White Sponge Nevus is KRT4 (Keratin 4), and among its related pathways/superpathways are Nervous system development and COPI-independent Golgi-to-ER retrograde traffic. Affiliated tissues include tongue and skin, and related phenotypes are FOXO1 nuclear localization and integument