Methionine Adenosyltransferase Deficiency: New Enzymatic Defect Associated with Hypermethioninemia

Abstract
A specific deficiency of methionine adenosyltransferase has been demonstrated in the liver of an infant with hypermethioninemia. Since the enzymatic activity was below that in fetal liver and the metabolic abnormality has persisted (the infant now being 1 year of age), there is probably a genetic mutation. Mass screening for hypermethioninemia may uncover more such cases.