Choroidal coloboma in two members of a family.

A family with choroidal coloboma is reported. A 43-year-old Japanese woman with choroidal coloboma including the optic disk and extending to the inferior half of the fundus in both eyes had horizontal nystagmus, microcornea and mild cortical cataract in both eyes. Her 40-year-old younger sister had choroidal colobomas in both eyes and also a horizontal nystagmus, microcornea in both eyes and a mature cataract in the left eye. They had no systemic abnormalities. Their parents and 2 younger sisters showed neither ocular nor systemic abnormalities. Choroidal coloboma with iris coloboma has been reported frequently, but familial choroidal coloboma without involvement of the iris and with no systemic abnormalities is rare.