Gaa, encoding acid alpha-1,4-glucosidase, is a gene located on chromosome 17. Gaa plays a crucial role in catalyzing the hydrolysis of α-1,4 and α-1,6-glucosidic bonds of glycogen, with its function central to glycogen metabolism within lysosomes [1].

In Pompe disease, a rare autosomal recessive disorder, mutations in the Gaa gene lead to a deficiency of acid alpha-1,4-glucosidase. This deficiency results in lysosomal glycogen storage in multiple tissues, particularly muscle, causing limb-girdle muscle weakness and respiratory failure [1]. In a mouse model of Pompe disease (Gaa-/-mice), Gaa deficiency led to glycogen accumulation in distal airway cells, disrupting surfactant homeostasis and contributing to respiratory impairments [2].

In conclusion, Gaa is essential for normal glycogen metabolism. Insights from the Gaa-/-mouse model have been valuable in understanding the pathogenesis of Pompe disease, specifically highlighting the role of Gaa deficiency in respiratory insufficiency through its impact on distal airway cells.