GJA1

The encoded protein forms connexin 43, the major gap junction protein that creates intercellular channels allowing diffusion of small molecules between cells, particularly important for synchronized cardiac contraction and embryonic development. Mutations cause oculodentodigital dysplasia, craniometaphyseal dysplasia, erythrokeratodermia variabilis et progressiva, and syndactyly through both autosomal dominant and autosomal recessive inheritance patterns. Disease can result from multiple mechanisms including gain-of-function effects from specific mutations that disrupt normal gap junction function.