Abstract
Purpose: :
Various lines of evidence demonstrate the involvement of mitochondrial dysfunction in the pathogenesis of glaucoma. Therefore, mitochondrial DNA is a promising candidate for genetic susceptibility studies on glaucoma. To test the hypothesis that mitochondrial haplogroups influence the risk to develop glaucoma, the frequencies of ten major European mitochondrial haplogroups were determined in healthy controls and two patient cohorts with either exfoliation glaucoma or the normal tension subgroup of primary open angle glaucoma.
Methods: :
The entire study population comprised 678 subjects of German origin including 272 patients with normal tension glaucoma, 157 patients with exfoliation glaucoma and 249 healthy controls. Twelve single-nucleotide polymorphisms that define ten major European mitochondrial DNA haplogroups were genotyped in all subjects by means of a capillary-based electrophoretic separation of multiplex primer extension products. Frequencies of mitochondrial haplogroups in patients and controls were tested for independence using Fisher’s exact test.
Results: :
Mitochondrial haplogroup U was significantly under-represented in patients with exfoliation glaucoma (8.3% compared with 18.9% in controls; p = 0.004). In patients with normal tension glaucoma, mitochondrial haplogroup U was slightly under-represented (13.2 % compared to 18.9% in controls) whereas mitochondrial haplogroup T was slightly over-represented (14.7% compared to 10.8% in controls). However, these differences did not reach significance level.
Conclusions: :
In the German population, people with mitochondrial haplogroup U have a lower risk to develop exfoliation glaucoma. Our results substantiate the suggestion that mitochondrial alterations have an impact on the etiology of glaucoma.
Keywords: gene screening • mitochondria