MTHFR is an abbreviation for a gene that codes for an enzyme called methyltetrahydrofolate reductase. The MTHFR enzyme helps the body to manufacture proteins. Mutations in the MTHFR gene are associated with thromboembolic and cardiovascular disease, which can lead to blood clots, strokes, embolisms, and heart attacks.
Two mutations of MTHFR are the most common. Approximately 30-40% of the population carries a mutation at position C677T, and 20% of the population carries a mutation at position C1298T. Individuals with these mutations are at increased risk for thromboembolic and cardiovascular disease. They are also linked with recurrent miscarriages and neural tube defects (NTD) in children of women carrying the mutations.