Symptoms of glycogen excess are varied and may include muscle weakness, motor difficulties, poor reflexes, spinal curvature and heart muscle damage. The incidence varies among different ethnic groups throughout the world.

Pompe disease can be caused by hundreds of different mutations in the GAA gene, which encodes an enzyme called acid alpha-glucosidase. This enzyme is necessary to break down the complex sugar glycogen into simple sugars, such as glucose, to be used by cells to produce energy.

Pompe disease is inherited in an autosomal recessive manner. This means that two copies of the defective gene are required for symptoms to manifest in an individual. Visit our Pompe disease inheritance page for more information.

Three main types of Pompe disease have been identified, depending on the age of onset and severity of the disease. They are called classical infantile-onset Pompe, non-classical infantile-onset Pompe and late-onset Pompe. Pompe disease is inherited, but cannot be acquired through physical contact with the affected person.

The infantile forms of Pompe disease can often be fatal, and immediate attention is essential at the time of diagnosis. The late-onset form is usually milder and progresses slowly.

There is currently no cure for Pompe disease, but its symptoms can be controlled and several treatment options are available. These include enzyme replacement therapy (ERT) and physical and occupational therapy. Several experimental therapies, such as gene therapy and companion therapy, are also being studied and tested.