G6PC1 and hyperlipidemia: GSD I is an autosomal recessive inborn error of carbohydrate metabolism caused by defects of the glucose-6-phosphatase complex.[2] Deficiency of glucose-6-phosphatase activity in the liver, kidney, and intestine results in the accumulation of glycogen in these organs.[2] As a result of inadequate glucose production, patients have severe fasting hypoglycemia with secondary biochemical abnormalities: hyperlactacidemia, hyperuricemia, and hyperlipidemia.[2] The incidence of GSD I in the overall population is 1/100,000.[1]