LOCALIZATION OF A LOCUS (GLC1B) FOR ADULT-ONSET PRIMARY OPEN-ANGLE GLAUCOMA TO THE 2CEN-Q13 REGION

Primary open angle glaucoma (GLC1) is a common ocular disorder with a characteristic degeneration of the optic nerve and visual field defect s that is often associated with an elevated intraocular pressure, The severe but rare juvenile-onset type has previously been mapped to 1q21 -q31, and its genetic heterogeneity has been established. Herein, we p resent a new locus (GLC1B) for one form of GLC1 on chromosome 2cen-q13 with a clinical presentation of low to moderate intraocular pressure, onset in late 40s, and a good response to medical treatment. Two-poin t and haplo-type analyses of affected and unaffected meioses in six fa milies provided maximum linkage information with D2S417, GATA112EO3, D 2S113, D2S373, and D2S274 (led scores ranging from 3.11 to 6.48) withi n a region of 8.5 cM that is flanked by D2S2161 and D2S2264. Analysis of affected meioses alone revealed no recombination with an additional two markers (D2S2264 and D2S135) in a region of 11.2 cM that is flank ed by D2S2161 and D2S176. Analysis of unaffected meioses identified on ly one healthy 86-year-old male who has inherited the entire affected haplotype and, hence, is a gene carrier for this condition. Eight addi tional families with similar and/or different clinical presentation di d not show any linkage to this region and, therefore, provided evidenc e for genetic heterogeneity of adult-onset primary open angle glaucoma . (C) 1996 Academic Press, Inc.