Abstract: More and more study shown that folate had important role in the pathophysiology of Down Syndrome. Folate level in patients with Down syndrome is lower than that in normal persons. Folate supplemented in pregnant women with the appropriate dose can reduce the risk of down syndrome. Folate plays an important role in DNA synthesis and methylation. It is not decided whether polymorphism of enzyme genes involving folate metabolism cause chromosome breakage and nondisjunction which increased the risk of Down Syndrome. In this article, we discussed the relationship between polymorphisms of enzyme genes involving folate metabolism and risk of Down Syndrome.

Key words: Folic acid, Down syndrome, Metabolism, Methylation, Polymorphism, genetic, Mutation