GJA1 and oculodentodigital dysplasia: Connexin 43 (GJA1, OMIM:121014) is located on chromosome 6 (6q21-q23.2) [50] of the human genome and has been implicated in a number of diseases but mainly in oculodentodigital dysplasia [124,125,126] with pleiotropic phenotypes [127].