GJB2 and Clouston syndrome: Two rare congenital disorders, keratitis–ichthyosis–deafness (KID) syndrome [OMIM 148210] and Clouston syndrome (hidrotic ectodermal dysplasia 2) [OMIM 129500], are caused by mutations in genes coding connexin proteins (GJB2 and GJB6, respectively), and both of them have skin manifestation.