Oculodentodigital dysplasia (ODDD) is caused by mutations in the GJA1 gene, which encodes Gap junction alpha-1 protein also known as connexin-43. The majority of cases are autosomal dominant (MIM 164200), but ODDD can also be autosomal recessive (MIM 257850). ODDD is characterized by abnormalities of the face, eyes, dentination, and digits of hands and feet. Typical findings include long, narrow nose, hypoplastic nasal alae, microcornea, microphthalmia, short palpebral fissures, cataract, iris anomalies, and syndactyly of 4th - 5th fingers. Additional findings may include cardiac defects, conductive hearing loss, anomalies of the skin, hair and nails, and neurological manifestations such as paraparesis, ataxia, spasticity, dysarthria, seizures and neurogenic bladder.

Autosomal recessive mutations in the GJA1 gene can also cause hypoplastic left heart syndrome 1 (HLHS1; MIM 241550), which results from defective development of the aorta proximal to the entrance of the ductus arteriosus. Hypoplastic left heart syndrome 2 (HLHS2; MIM 614435) is an autosomal dominant disorder, caused by mutation in the NKX2-5 gene.