Adult-onset primary glaucoma and molecular genetics: a review.

PURPOSE To evaluate recent molecular genetic studies focused on localizing and identifying the genes involved in adult-onset primary glaucoma, characterizing the gene products, and investigating the molecular mechanisms implicated in the pathophysiology of the disease. METHODS Several studies have aimed at understanding gene expression and protein processing and attempting to correlate the mutations identified in the involved genes, particularly the TIGR/MYOC gene, with the overall spectrum of the disease, ranging from juvenile glaucoma to typical late-onset primary open-angle glaucoma. Genetic research remains essential until highly specific and sensitive tests have been developed (plausible disease-causing sequence variations, polymorphisms). RESULTS The most effective method for detecting glaucoma clinically is the study of optic nerve and visual field damage, as well as intraocular pressure. In subjects at high risk, in members of families with a strong history of inherited glaucoma, and in families with a MYOC-positive test, the result may represent a marker to assess presymptomatic diagnosis and may be useful as a prognostic marker. CONCLUSIONS OPTN seems to have a role confined to the pathogenesis of normotensive glaucoma with a few exceptions. Presently, the introduction of the expensive and time-consuming OPTN gene test in the current diagnosis of familial glaucoma is not justified.