Danon disease

Danon disease, also called glycogen storage disease type IIb, is a metabolic disorder. It is an X-linked lysosomal and glycogen storage disorder, meaning it involves the lysosomes, the cell compartments that break material down, and the storage of glycogen. It is associated with hypertrophic cardiomyopathy, a thickening of the heart muscle, together with skeletal muscle weakness and intellectual disability. The disease is inherited in an X-linked dominant pattern, so a single altered copy of the responsible gene on the X chromosome is enough to be affected. The source lead does not give the name of the gene, the age of onset, or how the condition is managed, so this entry describes classification, main features and inheritance only and leaves further clinical detail for later work.