The neuropathology of the nonketotic and ketotic hyperglycinemias: three cases

Abnormal dysmyelination constitutes a pathoanatomic basis for the mental retardation in two different aminoacidopathies, nonketotic hyperglycinemia and ketotic hyperglycinemia. In both conditions myelin is decreased in amount and vacuolated. Similar patterns of dysmyelination in different aminoacidopathies suggest that abnormal myelination results from inadequate synthesis of myelin proteins.