Focal Facial Dermal Dysplasia, also known as ffdd, is related to aplasia cutis congenita and focal facial dermal dysplasia 3, setleis type. An important gene associated with Focal Facial Dermal Dysplasia is TWIST2 (Twist Family BHLH Transcription Factor 2). Affiliated tissues include skin and bone, and related phenotypes are Decreased viability and normal