Is MTHFR useful for Allergie?

Whether MTHFR is useful for allergies is not supported by strong evidence. MTHFR encodes an enzyme in folate metabolism; certain variants (e.g., C677T) can reduce enzyme activity. Some epidemiological studies have reported weak associations between MTHFR polymorphisms and elevated IgE levels or allergic conditions, but findings are small, inconsistent, and often not replicated. Effects are modulated by folate status, environment, and other genes. Direct-to-consumer DNA tests tend to overstate the clinical relevance of single SNPs. For allergy diagnosis or management, MTHFR testing currently has no established role. Specific allergy tests (IgE, skin prick) and a thorough history are far more informative. Evidence: mechanistic/weak; no guideline recommendation.