MTHFR Genotyping

The methylenetetrahydrofolate reductase (MTHFR) catalyzes the reaction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, which is involved in folate metabolism. The variant 677C>T in MTHFR gene causes production of a thermolabile enzyme with reduced enzymatic activity.

As a result, reduced conversion of homocysteine to methionine leads to an  accumulation of homocysteine in the plasma (hyperhomocysteinaemia). Enhanced homocysteine plasma concentration is a risk factor for coronary heart disease, thrombosis, and arterosclerosis. In addition, the variant MTHFR 1298A>C in the MTHFR gene has been associated with increased risk for cardiovascular diseases.

The presence of both variant (C677T and A1298C) in same patient is described as a risk factor for defects of the neural tube. MTHFR genotyping is an important pharmacogenomic test used to assess whether few therapies will be effective on patients who may have a MTHFR gene polymorphism as mentioned above.