Cornea plana may occur in connection with malformations of the eye or of other parts of the body. As an isolated ocular anomaly, it may be inherited in an autosomal recessive or in an autosomal dominant fashion. We have previously mapped genes for both forms of the disease to 12q21. We studied 36 members of three generations of a Black Cuban family with autosomal dominant cornea plana. Three affected males and 11 affected females were examined. Corneal refraction varied between 37.50 and 42.75 diopters. Horizontal corneal diameter ranged from 8.75 to 11.25 mm. The cornea was clear and the limbal zone only occasionally widened. A marked arcus senilis was present in six patients aged 30 to 58 years, but in none of their healthy relatives. The anterior chamber was shallow in those affected, varying in depth from 1.68 to 2.38 mm. One woman was blind from closed-angle glaucoma. The axial length was within normal limits in all patients.