The effect of MTHFR ala222val polymorphism on open-angle glaucoma: a meta-analysis.

Glaucoma is the second leading cause of irreversible blindness worldwide, among which primary open-angle glaucoma (POAG) is the most common form of glaucoma in some populations. To date, published data on the association between MTHFR (Ala222Val) polymorphism and POAG risk are still inconclusive. In this work, we performed a meta-analysis of available case-control study in order to assess the association between MTHFR (Ala222Val) polymorphism and POAG susceptibility. In total we compiled 13 studies (1970 POAG patients and 1712 control subjects) into the meta-analysis. Overall, no obvious associations between MTHFR (Ala222Val) polymorphism and POAG susceptibility was found under all four genetic models (Val/Val versus Ala/Ala: OR = 1.05, 95% CI = 0.77-1.43; Ala/Val versus Ala/Ala: OR = 1.05, 95% CI = 0.86-1.26; Ala/Val + Val/Val versus Ala/Ala: OR = 1.08, 95% CI = 0.87-1.34; Val/Val versus Ala/Val + Ala/Ala: OR = 1.14, 95% CI = 0.67-1.92). In the stratified analysis by ethnicity, significant associations were still not observed in all genetic models. In conclusion, based on 13 eligible studies, the result provided strong evidences that MTHFR Ala222Val polymorphism is not associated with POAG.