Methylenetetrahydrofolate reductase gene polymorphism and homocysteine level in patients with pseudoexfoliation and pseudoexfoliation glaucoma in southern Iran

ABSTRACT

Pseudoexfoliation [PEX] syndrome leads to elevated intraocular pressure and consequent glaucomatous damage of the optic nerve. This study was performed to investigate the frequency of MTHFR, 677 C-T polymorphism and homocysteine [Hcy] levels in Iranian patients with PEX and PEX glaucoma were compared to that in normal population. Thirty four patients with PEX, 27 with PEX and glaucoma, and 32 control subjects were enrolled. Pregnant patients with any systemic disorder such as hypertension and diabetes mellitus, usage of vitamin supplements or any condition affecting homocysteine level were excluded. Fasting total homocysteine [tHCT] levels of all the participants were determined, using an ELISA method and values exceeding 14 micromole /L were considered as an elevation. MTHFR genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism [PCR-RFLP]. Genotyping of polymorphism was done with polymerase chain reaction. The patients' mean age was 67 years [range 50-90 years] in all three groups and the male to female ratio was 21. The mean plasma homocysteine level was 13.95 +/- 8.7 in the PEX, 16.37 +/- 8.2 and 14.22 +/- 11.32 in the PEX glaucoma and the control group, respectively. The rate of C677T polymorphism was 44% in the PEX, 52% in the PEX glaucoma, and 40% in the control group. The result of this study implies that neither C677T polymorphism nor hyperhomocysteinemia can be considered as major risk factors for PEX or PEX glaucoma in Iranian population