» » McArdle disease

McArdle Disease - Symptoms - Diagnosis -Treatment - Prognosis

Rating : 12345
Rate This Article : 1 2 3 4 5
G J 4
A -A +


McArdle disease, also known as Glycogen storage disease type V, occurs due to a defect in the production of muscle phosphorylase.


McArdle disease is a genetic disorder in which the body cannot break down glycogen in the muscles. The disease results from a defect in a gene required for producing an enzyme called muscle phosphorylase (myophosphorylase). This enzyme is required to breakdown glycogen, an important source of energy that is stored in muscle tissue. This results in abnormal accumulation of glycogen in tissues.


McArdle disease (McArdle’s disease) is also known as McArdle syndrome or Glycogen storage disease type V (GSD-V). Its incidence is reported as 1 in 100,000.

McArdle disease is inherited in an autosomal recessive pattern, i.e. a copy of the defective gene from both parents is required for the child to develop the serious ailment. Many people carry one copy of the abnormal gene. Two abnormal copies are needed for McArdle disease to develop. Genetic mutations in the PYGM gene are found in individuals with McArdle disease.

McArdle disease is approximately equally represented in both sexes. Symptoms usually first develop in adulthood (sometimes early or late childhood). Exercise intolerance with muscle cramps is common. A definitive diagnosis usually requires a biochemical assay. No particular race is at a high risk of acquiring the disease.

In general, no permanent cure exists for McArdle disease. The role of a high protein diet in increasing exercise tolerance is controversial. The disease does not appear to affect longevity.

Post your Comments

Comments should be on the topic and should not be abusive. The editorial team reserves the right to review and moderate the comments posted on the site.
User Avatar
* Your comment can be maximum of 2500 characters
Notify me when reply is posted I agree to the terms and conditions

Ask an Expert

If you have a question about health related issues, you can now post it in our Ask An Expert section on our community website and get answers from our panel of experts.

You May Also Like

View All