ADULT-ONSET PRIMARY OPEN-ANGLE GLAUCOMA DOES NOT LOCALIZE TO CHROMOSOME 2CEN-Q13 IN NORTH-AMERICAN FAMILIES

Glaucoma is one of the leading causes of irreversible blindness in the world and is characterized by elevated intraocular pressure, optic ne rve atrophy, and progressive visual field loss. Primary open angle gla ucoma (POAG) is the most common subtype of glaucoma in the United Stat es. Recently, Stoilova and coworkers [Genomics 1996;36:142-150] identi fied a locus for POAG on chromosome 2 (2cen-q13) in families primarily located in the United Kingdom. We examined families with POAG identif ied within the US for linkage to the 2cen-q13 locus. A total of 18 fam ilies with POAG were used in the analysis. Of 77 family members, 46 we re classified as affected and 31 were either glaucoma suspects or cons idered normal. Eight highly polymorphic and informative markers flanki ng and distributed throughout the region were used. Parametric lod sco re analysis was performed using both a dominant and recessive low pene trance or 'affecteds-only' model. Multipoint affected sibpair exclusio n mapping was also performed. Lod score (both models) and sibpair anal ysis excluded linkage of the POAG phenotype to the 2cen-q13 region in these families. These data suggest that the chromosome 2cen-q13 locus does not explain a substantial amount of genetic variation in familial POAG.