Molecular Genetic Studies of Genes Predisposing for Glaucoma

University dissertation from Uppsala : Acta Universitatis Upsaliensis

Abstract: Glaucoma is one of the leading causes of visual impairment in the world. In glaucoma, the patient’s peripheral vision is lost due to progressive and irreversible deterioration of the retinal ganglion cells and atrophy of the optic nerve. The effect on the visual field is gradual and painless, and the progression so slow, that the patient may not notice until a substantial part of the visual field is lost. If left untreated, glaucoma can lead to blindness.In this thesis, genes associated to glaucoma have been analysed in Swedish patients with primary open angle and exfoliative glaucoma. The genes studied were MYOC, oculomedin, GSTM1 and OPTN.The coding sequence of MYOC was analysed and mutations were found in 1% of the primary open angle glaucoma patients. Additionally, a predisposing variant was found in 1% of the patients as well as in 0.5% of the controls. No disease-associated variation was found in the exfoliative glaucoma cases. Mutations were also found in two families affected by glaucoma. The coding sequence of oculomedin was analysed, but none of the variants found were classified as disease causing in either patient group. GSTM1 was analysed for its presence in the patients. No association could be found for either hetero- or homozygous deletions. The coding sequence and haplotype distribution of OPTN was analysed. None of the variants found were classified as disease causing and none of the haplotypes were associated to the disease in either patient group.There are just a few per cent of the Swedish primary open angle glaucoma patients with genetic variation associated to disease, in the genes analysed in this study. No association to exfoliative glaucoma was found. This indicates heterogeneity in the genetics of glaucoma when different subtypes and different populations are compared. Likely, there are genes still to be identified.