INTRODUCTION Glycogen-storage disease is a congenital defect of carbohydrate metabolism characterized by deficient glycolysis and associated glycogen accumulation in various organs, particularly the liver. Secondary manifestations relate to the primary site of involvement. When the defect is principally in the liver, there is a propensity for hypoglycemia and exaggerated lipogenesis with secondary ketosis. The hepatic form of the disease, the first described,* is severest when manifest in the neonatal period.† Various other clinical types of the syndrome, not to be considered in this publication, have been described.‡ Glycogen-storage disease appears to be familial, and the specific enzymatic defect or anomaly is presumably inherited as a simple recessive trait.§ This defect would appear to involve chiefly glucose-6-phosphatase. Substantial support for this thesis exists in the observations of Thannhauser and co-workers11and Cori and associates,‖ who demonstrated low or absent glucose-6-phosphatase activity in liver preparations from several cases of classical von