Mucopolysaccharidosis

Mucopolysaccharidosis is a group of autosomal recessive metabolic disorders 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.

People with a mucopolysaccharidosis either do not produce enough of one of the 11 enzymes required to break down these sugar chains into proteins and simpler molecules, or they produce enzymes that do not work properly. Over time, these glycosaminoglycans collect in the cells, blood and connective tissues. The result is permanent, progressive cellular damage which affects appearance, physical abilities, organ and system functioning, and, in most cases, mental development.

The mucopolysaccharidoses 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.