title: Molecular diagnostics of genetic eye diseases.
abstract: Eye diseases can be simple or complex, and mostly of heterogeneous molecular genetics. Some eye diseases are caused by mutations in a single gene, but some diseases, such as primary open angle glaucoma, can be due to sequence variations in multiple genes. In some diseases, both genetic and epigenetic mechanisms are involved, as was recently revealed in the mechanism of retinoblastoma. Disease causative mutations and phenotypes may vary by ethnicity and geography. To date, more than a hundred candidate genes for eye diseases are known, although less than 20 have definite disease-causing mutations. The three common genetic eye diseases, primary open angle glaucoma, age-related macular degeneration, and retinitis pigmentosa, all have known gene mutations, but these account for only a portion of the patients. While the search for eye disease genes and mutations still goes on, known mutations have been utilized for diagnosis. Genetic markers for pre-symptomatic and pre-natal diagnosis are available for specific diseases such as primary open angle glaucoma and retinoblastoma. This paper reviews the molecular basis of common genetic eye diseases and the available genetic markers for clinical diagnosis. Difficulties and challenges in molecular investigation of some eye diseases are discussed. Establishment of ethnic-specific disease databases that contain both clinical and genetic information for identification of genetic markers with diagnostic, prognostic, or pharmacological value is strongly advocated.
authors.affiliation: Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, 147K Argyle Street, Kowloon, Hong Kong.
authors.forename: Bao Jian
authors.initials: BJ
authors.lastname: Fan
authors.forename: Pancy Oi Sin
authors.initials: PO
authors.lastname: Tam
authors.forename: Kwong Wai
authors.initials: KW
authors.lastname: Choy
authors.forename: Dan Yi
authors.initials: DY
authors.lastname: Wang
authors.forename: Dennis Shun Chiu
authors.initials: DS
authors.lastname: Lam
authors.forename: Chi Pui
authors.initials: CP
authors.lastname: Pang
mesh_terms: D015785:Eye Diseases, Hereditary / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D005817:Genetic Counseling; D005819:Genetic Markers; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis
chemical_list: D005819:Genetic Markers