Glycogen storage disease type 1A (GSD1A), or von Gierke disease, is caused by a defect in the G6PC gene which codes for Glucose-6-phosphatase. Glucose-6-phosphatase hydrolyzes glucose-6-phosphate to glucose and is responsible for the regulation of blood glucose level. A defect in this enzyme results in accumulation of glycogen in affected tissues, like liver and kidney; decreased glucose level; and accumulation of lactate. Glycogen storage disease type 1A causes clinically significant end-organ disease with significant morbidity. Usually it presents in childhood. Symptoms include seizures, irritability, pallor, hypotonia, tremors, loss of consciousness, apnea and hepatomegaly. There is no cure for glycogen storage disease type 1A. Diet therapy can help to prevent hypoglycemia and reduce the symptoms. Liver transplantation may be indicated in cases of hepatic malignancy.