MTRR (Methionine Synthase Reductase): MTRR is an enzyme that plays a critical role in regenerating methylcobalamin, supporting the continuous function of MTR in homocysteine metabolism. It is essential for maintaining proper methionine levels and normal DNA synthesis. Mutations in MTRR are linked to homocystinuria, which can contribute to developmental and neurological complications. Understanding MTRR function provides insights for potential therapies for genetic disorders.