What is it?

Glycogen storage disease type Ia (GSDIa) is a genetic disorder that results in the buildup of glycogen in the body’s cells and an inability to regulate and maintain normal blood sugar levels. It is the most common type of genetically inherited glycogen storage disease.

What causes it?

GSDIa is caused by a defect in the enzyme glucose-6-phosphatase, which makes the body unable to convert the complex sugar glycogen (from foods such as carbohydrates) into glucose and regulate blood sugar.

What are some of the common symptoms?

  • Poor growth (failure to thrive) and developmental delays in infants
  • Hypoglycemia or low blood sugar (which can result in shakiness and lightheadedness)
  • Enlarged liver
  • Elevated lactate and uric acid levels in the blood and urine
  • Seizures
  • Renal failure (if left untreated)

How many people have it?

Approximately 6,000 or more patients in the developed world are affected by GSDIa.

Common names for GSDIa1

  • Von Gierke disease
  • Glycogenosis type 1
  • Glucose-6-phosphatase deficiency
  • Hepatorenal glycogenosis
  • Glucose-6-phosphatase deficiency glycogen storage disease
  • Glycogen Storage Disease Type 1a (GSD1a)

1Glycogen storage disease type 1A. National Institutes of Health: Genetic and Rare Diseases Information Center Website. https://rarediseases.info.nih.gov/diseases/7864/glycogen-storage-disease-type-1a. Updated March 1, 2019. Accessed March 29, 2019.

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