Role of MTHFR in Retinal Vascular Occlusion (RVaO)

Abstract

Abstract: : Purpose: RVaO, the second most common retinal vascular disease after diabetic retinopathy has multifactoral etiology. Our prospective case controlled study was designed to determine the role of methylene tetrahydrofolate reductase (MTHFR) gene mutation in RVaO. Methods: 71 consecutive patients presenting with RVaO diagnosed clinically at LSU eye clinic from February 2000 to 2003 were included in this study. 73 age, sex and race matched controls without RVaO were selected from the same clinic during this period. Blood was processed for MTHFR mutation (C677–T) by PCR using Microplate multiplex AS–PCR analysis with Perkin–Elmer 9700 model PCR machine. Results:A total of 71 study patients and 73 control patients were included in the study. Our study group was predominantly females (61%) and older (mean age = 62 years). There were 55 blacks (75%) and 16 whites included in the study group compared to 59 blacks and 14 whites in the control. Incidence of MTHFR gene mutation (homozygous + heterozygous) was 45% in the disease group (36% black, 75% white) and 27 % in our control (23% black, 42% white) population (p=0.042). There were only two patients and 3 controls that carried a homozygous MTHFR gene mutation. 46% of patients with branch retinal vein occlusion (BRVO, total=30), {28% black and 89% white}; 50% of patients with central retinal vein occlusion (CRVO, total=22), {50% black and 50% white} and 37 % of patients with retinal artery occlusion (RAO, total=19), {28% black (p=0.054) and 60% white} carried a MTHFR gene mutation. Conclusions: We propose that presence of MTHFR gene mutation is associated with RVaO (p=0.042).A larger patient sample population is needed to see whether there is correlation between homozygous MTHFR gene mutation and RVaO.

Keywords: vascular occlusion/vascular occlusive disease • gene screening • clinical (human) or epidemiologic studies: risk factor assessment