Focal Facial Dermal Dysplasia 4, also known as focal facial dermal dysplasia type iv, is related to focal facial dermal dysplasia 1, brauer type and focal facial dermal dysplasia 3, setleis type. An important gene associated with Focal Facial Dermal Dysplasia 4 is CYP26C1 (Cytochrome P450 Family 26 Subfamily C Member 1). Affiliated tissues include skin, and related phenotypes are abnormal blistering of the skin and abnormal cheek morphology