['To present the phenotype of a family whose members showed the Gly367Arg mutation in the myocilin gene and developed primary open-angle glaucoma (POAG).', 'The proband developed POAG when she was 45 years old. Examination of the myocilin gene revealed that the patient had a mutation causing amino-acid change (Gly367Arg) in the myocilin gene. The available family members were given clinical and genetic examinations.', 'Eight members of this family carried the same mutation. The age of disease onset of POAG in these patients with the mutation averaged 36.7 years. Four young members with the mutation, with an average age of 20.8 years, had not yet developed POAG.'] Does the Gly367Arg mutation in the myocilin gene cause adult-onset primary open-angle glaucoma?