Variable expressivity of hypertelorism in three siblings with Greig syndrome.

Two sisters and one brother are reported with a complex of congenital malformations, hypertelorism, mental retardation, flattened nasal root, divergent strabism++, mongoloid palpebral fissures, malformations of the ears, pathologic alterations of the eye-fundus in terms of optic nerve atrophy, all suggesting Greig syndrome. The major symptom of this syndrome, the hypertelorism, varied considerably in its expressivity in the three siblings. This fact is normally taken into consideration in the diagnosis of Greig syndrome, but we suggest that an alteration in skull formation should be the criterion for the syndrome rather than extreme hypertelorism.