Association of MTRR A66G polymorphism (but not of MTHFR C677T and A1298C, MTR A2756G, TCN C776G) with homocysteine and coronary artery disease in the French population

methylenetetrahydrofolate reductase polymorphism (MTHFR C677T) is an established determinant of homocysteine plasma level (t-Hcys) while its association with coronary artery disease (CAD) seems to be more limited. In contrast, the association of the substitutions A2756G of methionine synthase (MTR), A66G of methionine synthase reductase (MTRR) and C776G of transcobalamin ( TCN) to both t-Hcys and CAD needs to be evaluated further.The objective was to evaluate the association of these polymorphisms with t-Hcys and CAD in a French population. We investigated the individual and combined effects of these polymorphisms and of vitamin B12 and folates with t-Hcys in 530 CAD patients and 248 matched healthy controls. t-Hcys was higher in the CAD group than in controls (11.8 vs 10.4 µ M, P median and MTRR AA genotype were two significant independent predictors of CAD with respective odds ratios of 3.1 (95 % CI: 1.8–5.1, P