McArdle disease mutations and polymorphisms

Abstract

McArdle disease is an autosomal recessive disorder caused by inherited deficiency of the muscle isoform of glycogen phosphorylase (or ‘myophosphorylase’), which catalyzes the first step of glycogen catabolism, releasing glucose-1-phosphate from glycogen deposits. As a result, muscle metabolism is impaired, leading to different degrees of exercise intolerance. Patients range from asymptomatic to severely affected, including in some cases limitations in activities of daily living. This genetic disorder is caused by mutations in the PYGM gene.