Two novel mutations in acid alpha-glucosidase gene in two patients with Pompe disease

Pompe disease is an autosomal recessive lysosomal glycogen storage disorder (GSD) caused by acid alpha-glucosidase (GAA) deficiency. Pompe disease has a broad genotypic and phenotypic spectrum. The infantile-onset form is the most severe form and presents with hypotonia and cardiomyopathy in early infancy. The probands who died were found to have GSD type II based on clinical and biochemical findings. We report two families with Pompe disease in whom the parents' molecular analysis revealed two novel mutations: c.2045A>G (p.Q682R) and c.763C>T (p.Q255X).