Retinal vein occlusion, homocysteine, and methylene tetrahydrofolate reductase genotype.

Purpose: The aim of this case-control study was to investigate the relationship between homocysteine (tHcy), 5,10 methylene tetrahydrofolate reductase (MTHFR) C677T genotype, folate and vitamin B12 status, and retinal vein occlusion (RVO).

Methods: Subjects with RVO (n = 106) were recruited from outpatient and inpatient sources. Controls (n = 98) were selected to achieve a similar age and sex distribution.