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Published on: July 14, 2016
Plasma homocysteine, MTHFR gene mutation, and open-angle glaucoma
Colin I Clement1, Ivan Goldberg, Paul R Healey
1Department of Ophthalmology, Sydney Eye Hospital, Sydney, Australia. colinc1@gmp.usyd.edu.au
Journal of Glaucoma
|January 15, 2009
Summary
Elevated plasma homocysteine was observed in patients with pseudoexfoliation glaucoma (PXFG), primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG). This suggests a link between high homocysteine levels and glaucoma development.
Area of Science:
- Ophthalmology
- Cardiovascular Disease Research
- Medical Genetics
Background:
- Elevated plasma homocysteine is a known risk factor for cardiovascular disease.
- Recent research suggests a potential link between homocysteine and glaucoma pathogenesis.
- Previous studies show inconsistent findings regarding homocysteine levels in different types of open-angle glaucoma.
Purpose of the Study:
- To investigate plasma homocysteine levels in patients with pseudoexfoliation glaucoma (PXFG), primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG).
- To examine the association between the C677T methylenetetrahydrofolate reductase (MTHFR) gene mutation and glaucoma.
- To determine if elevated homocysteine is a common factor in these glaucoma subtypes.
Main Methods:
- A prospective cross-sectional cohort study was conducted.
- Participants included 48 PXFG, 36 POAG, 34 NTG patients, and 42 healthy controls.
- Fasting blood samples were analyzed for plasma homocysteine and MTHFR C677T gene mutation.
Main Results:
- Mean plasma homocysteine levels were significantly higher in all glaucoma groups (PXFG, POAG, NTG) compared to controls.
- Hyperhomocysteinemia was present in 27.1% of PXFG, 30.6% of POAG, and 29.4% of NTG patients.
- No significant difference in the frequency of the MTHFR C677T gene mutation was found among the groups.
Conclusions:
- Plasma homocysteine levels are elevated in patients with PXFG, POAG, and NTG.
- Elevated homocysteine appears to be associated with glaucoma in these patient populations.
- The MTHFR C677T mutation does not explain the elevated homocysteine levels in these glaucoma types.
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