Acid alpha-glucosidase, also called acid maltase, [5] is an enzyme that helps to break down glycogen in the lysosome. It is functionally similar to glycogen debranching enzyme, but is on a different chromosome, processed differently by the cell and is located in the lysosome rather than the cytosol. [6] In humans, it is encoded by the GAA gene. [5] Errors in this gene cause glycogen storage disease type II (Pompe disease).
This gene encodes lysosomal alpha-glucosidase, which is essential for the degradation of glycogen to glucose in lysosomes. Different forms of acid alpha-glucosidase are obtained by proteolytic processing. Defects in this gene are the cause of glycogen storage disease II, also known as Pompe disease, which is an autosomal recessive disorder with a broad clinical spectrum. Three transcript variants encoding the same protein have been found for this gene. [5]