Abstract
Abstract: :
Purpose: To investigate the TIGR/MYOC/GLC1A gene for disease associated alleles in Swedish cases with primary open angle glaucoma (POAG), exfoliative glaucoma and unaffected controls. Mutations in this gene have previously been found in families with juvenile glaucoma and some cases with POAG. Methods: DNA from 200 cases with POAG and 200 cases with exfoliative glaucoma were screened for allelic variants in the three exons of the GLC1A gene using both enzymatic mismatch cleavage and denaturing HPLC (dHPLC). DNA from 200 controls matched for age, sex and ethnicity, in which the diagnosis of glaucoma was excluded by physical examination, were screened using dHPLC. Results: Eight allelic variants were found in 101 of the 400 cases. The two variants Thr285Met and Pro481Arg were found once each among POAG cases and were determined to be disease associated. The Gln368STOP variant was detected in two POAG cases and in one unaffected control who was 82 years old. This indicates that the pathogenic effect of this allele is questionable and underscores similar findings in other studies. A Thr256Met allele was found in a 77 years old, unaffected control. Even though this is a substantial amino acid substitution it is apparently not associated with disease. No disease causing mutations were found in the cases with exfoliative glaucoma. Conclusion: Disease causing mutations in the GLC1A gene are less common in Swedish POAG cases than in other populations. Care must be taken when assigning disease status to an allele, illustrated by the fact that Gln368STOP and Thr256Met were found in old unaffected controls. There is no evidence that the GLC1A gene is involved in the genetic predisposition to exfoliative glaucoma.
Keywords: 420 genetics • 480 mutations