Methylenetetrahydrofolate Reductase Deficiencies
Bios364--Molecular Genetics
Dr. Chet Fornari, Professor
DePauw University
May 10, 2001
Human
methylenetetrahydrofolate reductase (MTHFR) is a key cytoplasmic enzyme
in the folate metabolism pathway (Figure
1).
It utilizes the cofactor flavin adenine dinucleotide (FAD) and
substrate NADPH to catalyze the conversion of
5,10-methylenetetrahydrofolate (CH2-H4folate) to
5-methyltetrahydrofolate (CH3-H4folate):
CH2-H4folate
+ NADPH
à
CH3-H4folate
+ NADP +
The CH3-H4folate product is then used by methionine synthase as a methyl donor in the reaction converting homocysteine to methionine. Any failure of MTHFR to adequately perform its reaction causes a low supply of this necessary methyl donor and leads to a build-up of homocysteine.
Several conditions have been linked to a deficiency in MTHFR. The purpose of this web page is to describe the genetic, molecular, and biochemical basis of these conditions. Please select a topic from the links below to learn all about it!!