There seems great variability in symptoms, some patients experiencing muscle issues, others with heart involvement.  Symptoms commonly present in adulthood, with progressive muscle weakness and exercise intolerance.
Estimated cases diagnosed worldwide: <10.



Dizziness and palpitations following exercise. Asymmetric and distal limb muscle weakness. Normal baseline CK.


Cardiac arrhythmia. Progressive muscle weakness. 


 Child or adult.


Skeletal muscle.


No specific treatment.


Not yet known.

IAMGSD would welcome hearing from patients or doctors who could help us to improve and expand our information on this extremely rare muscle GSD.


Affected individuals are assessed on an individual basis and treated according to their symptoms.


It is very likely that with the advent of Next Generation Sequencing and a gene panel for conditions which can be the cause of rhabdomyolysis, more cases of GSD15 will be identified. As understanding of the condition grows, IAMGSD will be able to offer better support for this extremely rare muscle GSD.

What is IamGSD?

We are a patient-led international group encouraging efforts by research and medical professionals, national support groups and individual patients worldwide.

What is Muscle GSD?

Human bodies make glucose from carbohydrates. Excess glucose is stored as glycogen in our muscles and liver. Muscle glycogen storage disease is when our muscles cannot convert their glycogen back into glucose to power our muscles.

Muscle GSDs links
If you have another muscle GSD please contact us.

Site updated: 04/2021.

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