Fig. 1From: Riboflavin status modifies the effects of methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms on homocysteineIllustration of the roles of MTHFR and MTRR in the folate cycle and homocysteine remethylation. SHMT serine hydroxymethyltransferase, MTHFR methylenetetrahydrofolate reductase, MS methionine synthase, MTRR methionine synthase reductase, THF tetrahydrofolate; CH 2 THF 5,10-methylenetetrahydrofolate, CH 3 THF 5-methyltetrahydrofolate. Circles indicate enzymes that require riboflavin (B2) or vitamin B6Back to article page