MTHFR is an enzyme that helps process folate, a form of vitamin B. Folate plays an important role in DNA synthesis and the regulation of homocysteine levels. Major substrates include methotrexate, a drug commonly used in chemotherapy and rheumatoid arthritis treatment. Patients who are initiating folate or methotrexate therapies or have a history of adverse effects or treatment failure should consider MTHFR genotyping. Genetic variants tested for MTHFR are c.665C>T (c.677C>T), c.1286A>C (c.1298A>C).
Indication for MTHFR Testing
Individuals with a personal or family history of adverse drug effects to methotrexate. In these cases, it’s critical to confirm the presence of genotypes that affect the metabolism of drugs that are metabolized by this pathway.