MTRR (Methionine Synthase Reductase): MTRR is an enzyme that plays a vital role in regenerating methylcobalamin, supporting the ongoing function of MTR in homocysteine metabolism. It is crucial for maintaining proper methionine levels and normal DNA synthesis. Mutations in MTRR are associated with homocystinuria, which can lead to developmental and neurological complications. Understanding MTRR function offers insights into potential therapies for genetic disorders.