TY - CHAP M1 - Book, Section TI - Primary Open Angle Glaucoma A1 - Wiggs, Janey L. A2 - Murray, Michael F. A2 - Babyatsky, Mark W. A2 - Giovanni, Monica A. A2 - Alkuraya, Fowzan S. A2 - Stewart, Douglas R. PY - 2014 T2 - Clinical Genomics: Practical Applications in Adult Patient Care AB - Disease summary:Primary open angle glaucoma (POAG) is a genetically and clinically complex disease with multiple genetic risk factors and environmental exposure influencing disease susceptibility.POAG is defined by progressive degeneration of the optic nerve. Elevation of intraocular pressure (IOP) is a risk factor for optic nerve degeneration, however, approximately 30% of POAG patients have optic nerve degeneration despite IOPs in the normal range (called normal-pressure glaucoma or NPG, also normal-tension glaucoma or NTG).Ocular traits other than IOP also contribute to POAG risk including the thickness of the central cornea, the size of the optic nerve (optic nerve area), and the size of the optic nerve “cup” relative to the overall size of the nerve (optic nerve cup-to-disc-ratio, CDR).Differential diagnosis:Exfoliation glaucoma, pigment dispersion glaucoma, developmental glaucoma, angle-closure glaucomaMonogenic forms:Autosomal dominant juvenile-onset primary open-angle glaucoma caused by mutations in the MYOC gene.Family history:Siblings and first-degree relatives have a 7 to 10 times increased risk of developing POAG overall.Twin studies:Monozygotic twins have an increased risk of disease when compared to dizygotic twins.Environmental factors:Postmenopausal hormone use and body mass index (BMI) have been suggested as environmental risk factors for POAG.Genome-wide associations:Genome-wide association studies (GWAS) have identified five genes or loci for POAG: CDKN2BAS (POAG and NPG), CAV1/CAV2 (POAG), TMCO1 (POAG), SIX1/SIX6 (POAG), and 8q22 (NPG). GWAS for ocular quantitative traits relevant to POAG have also yielded results: CDKN2BAS (CDR), SIX1/SIX6 (CDR), ATOH7 (optic nerve area), and a number of genes or loci for central corneal thickness (CCT), a trait that is a risk factor for the disease. Disease-associated genetic variants (single-nucleotide polymorphisms [SNPs]) have provided insight into disease pathogenesis; testing for SNPs is not yet clinically validated to diagnose or guide management of POAG.Pharmacogenomics:Testing for common variants has not yet been shown to influence management of POAG. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/10/09 UR - accessbiomedicalscience.mhmedical.com/content.aspx?aid=1102706205 ER -