GJA1 and hereditary palmoplantar keratoderma: These epidermal pathologies overlap considerably with the dermatological phenotype of human patients carrying the Cx43-E227D, or Cx43-A44V mutations causing erythro-keratodermia variabilis et progressive (EKVP) [26], or patients carrying the Cx43-G8V mutation causing palmoplantar keratoderma and congenital alopecia-1 (PPKCA1) [27].