Gap Junction Protein Alpha 8 (GJa8)

GJa8 encodes a transmembrane connexin protein that is necessary for lens growth and maturation of lens fiber cells. The encoded protein is a component of gap junction channels and functions in a calcium and pH-dependent manner. Mutations in this gene have been associated with zonular pulverulent cataracts, nuclear progressive cataracts, and cataract-microcornea syndrome.Defects in GJA8 are the cause of cataract-microcornea syndrome. Cataract-microcornea syndrome is characterized by the association of congenital cataract and microcornea without any other systemic anomaly or dysmorphism. Clinical findings include a corneal diameter inferior to 10 mm in both meridians in an otherwise normal eye, and an inherited cataract, which is most often bilateral posterior polar with opacification in the lens periphery.