The interactions of nine dominant Cx26 mutants, six associated with non-syndromic hearing loss, including p.Trp44Cys and p.Trp44Ser, and three associated with hearing loss and palmoplantar keratoderma, were investigated by immunocytochemistry, co-immunoprecipitation, and functional assays [133,134]. This evidence concerns the gene GJB2 and hereditary palmoplantar keratoderma.