The<unk>  are a group of inherited metabolic diseases caused by the absence or malfunctioning of lysosomal enzymes needed to break down molecules called glycosaminoglycans - long chains of sugar carbohydrates in each of our cells that help build bone, cartilage, tendons, corneas, skin and connective tissue. Glycosaminoglycans (formerly called mucopolysaccharides) are also found in the fluid that lubricates our joints.
The<unk>  are classified as lysosomal storage diseases. These are conditions in which large numbers of molecules that are normally broken down or degraded into smaller pieces by intracellular units called lysosomes accumulate in harmful amounts in the body's cells and tissues, particularly in the lysosomes.
Mucopolysaccharidosis
Glycogen storage disease
Sphingolipidoses
GM1 gangliosidoses
Ceroid storage disease
Glycogen storage disease type I
Glycogen storage disease type III
Glycogen storage disease type II