Oculodentodigital dysplasia with mandibular retrognathism and absence of syndactyly: a case report with a novel mutation in the Connexin 43 gene

Oculodentodigital dysplasia (ODDD) is a rare, autosomal dominant pleiotropic disorder, caused by mutations in the Connexin 43 (Cx43 or GJA1) gene. Described here is the case of a 10-year-old girl with enamel hypoplasia, typical facies and mental delay, initially thought to be related to an unknown metabolic disorder. Careful clinical re-evaluation revealed a type of ODDD, characterised by the predominance of facial and ophthalmological involvement with mandibular retrognathism, and by the absence of cutaneous hand or foot syndactyly. A novel single-sequence variation (Nt460A>G) in exon 2, resulting in the substitution of alanine for threonine at amino acid 154, was found. These findings confirm once again the highly variable phenotypic expression caused by Cx43 mutations.