A type of lysosomal storage disease that is caused by a pathological mutation in HYAL1 gene thereby affecting the production of enzyme hyaluronidase essential in breaking down mucopolysaccharides (particularly, hyaluronan) and as such leads to symptoms associated with this condition
Lysosomal storage disease is a collective term for the various metabolic disorders due to defects in lysosomal function resulting in an abnormal accumulation of toxic materials in the cell. One of them is mucopolysaccharidosis, a condition due to the accumulation of mucopolysaccharides (now referred to as glycosaminoglycans) in the lysosomes.
Mucopolysaccharidosis type IX is one of the many types of mucopolysaccharisosis. It is particularly caused by a pathological mutation in HYAL1 gene resulting in the deficiency of an enzyme that catalyzes the breakdown of mucopolysaccharides in the lysosomes. The gene normally codes for the production of hyaluronidase. This lysosomal enzyme takes part in the degradation of hyaluronan. Hyaluronan is a glycosaminoglycan component of the extracellular matrix. The condition is inherited in autosomal recessive manner.
Individuals with mucopolysaccharidosis type IX is characterized by multiple soft-tissue masses. Other distinctive features include bifid uvula, submucosal cleft palate, flat nasal bridge, short stature, acetabular erosions, joint effusion, etc.
- hyaluronidase deficiency