DEMYELINATION AND INBORN-ERRORS OF THE SINGLE CARBON TRANSFER PATHWAY

Inborn errors of the single-carbon transfer pathway are rare disorders of folate and cobalamin metabolism. They may be complicated by demyel ination resembling subacute combined degeneration of the cord and brai n, The study of CSF metabolites in children with serial errors affecti ng the single-carbon transfer pathway has suggested that S-adenosylmet hionine thionine deficiency is a cause of the demyelination, This defi ciency is corrected by treatment that causes clinical improvement and remyelination. Some treatments can only have an indirect effect on the brain and this is discussed with other evidence that the liver may pr oduce factors that are necessary for the maintenance of central myelin .