Remethylation of homocysteine to methionine is dependent on an adequate supply of one or more of the B vitamins like folate, vitamin B(12) and vitamin B(6). Plasma total homocysteine (tHcy) is also influenced by genetic factors such as polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene. MTHFR is a flavo enzyme and a key player in folate metabolism and changes in its activity could modify the susceptibility to Acute Lymphoblastic Leukemia (ALL). In this case - control study we have examined the effect of riboflavin status as measured by erythrocyte glutathione reductase activation coefficient (EGRAC) on homocysteine levels along with vitamin B(12) and folate in pediatric ALL. Folate and B(12) levels were significantly lower among cases as compared to controls while EGRAC and tHcy did not differ significantly among the groups. The multivariate regression analysis revealed that in the ALL group EGRAC significantly influences tHcy levels suggesting that riboflavin availability may be a predictor of tHcy levels in patients with ALL. This finding may have implications for tHcy lowering therapy.
Keywords: Acute Lymphoblastic Leukemia; Homocysteine; MTHFR; Riboflavin.