MPS IX (Natowicz Syndrome)
Also known as: Mucopolysaccharidosis IX, Natowicz syndrome, Hyaluronidase deficiency
Taraasha Foundation
Disease Information Sheet: MPS IX (Natowicz Syndrome)
What is it?
MPS IX is caused by a mutation (change) in the HYAL1 gene. This leads to a deficiency in an enzyme called hyaluronidase which is needed to breakdown mucopolysaccharide hyaluronan. When hyaluronan is not broken down entirely, it stays stored in the body. This build-up of hyaluronan in the tissues in the body causes the symptoms associated with the condition. Babies usually show little sign of the condition, but as more and more cells build up, symptoms start to appear.
How common is it?
MPS IX is an extremely rare condition that was first noted in 1996. Only one case of MPS IX has been reported to date.
Signs & Symptoms
Symptoms of MPS IX may include:
• Mild short stature
• Cysts
• Frequent ear infections
• Cleft palate
• Flattened nose bridge
• Development of soft-tissue masses
*However, more cases of MPS IX must be identified before a clear clinical picture of symptoms can be established.
Causes & Inheritance
Mutation in the HYAL1 gene.
MPS IX is an inherited condition. Humans have chromosomes made up of DNA. Genes are pieces of DNA that carry the genetic information. Each chromosome may have several thousand genes. We inherit chromosomes from the egg of the mother and sperm of the father. The genes on those chromosomes carry the instructions that determine a person’s characteristics, which are a combination of the parents.
The pattern of inheritance of MPS IX is autosomal recessive. This means that carriers of the condition do not have the disorder because the other gene of this pair is working normally. Parents of children with MPS IX are carriers.
When both parents are carriers, the risk to the baby in each pregnancy is
• 25% chance (1 in 4) of developing the condition
• 50% chance (1 in 2) for the baby to be a carrier of the condition
• 25% chance (1 in 4) for the baby to have two working genes and neither have the condition nor be a carrier
Genetic counselling can be requested to get a full explanation.
Diagnosis
Enzyme assays (testing a range of cells or blood in culture for enzyme deficiency) are used to provide a diagnosis. Individuals with the condition will show a deficiency in the enzyme hyaluronidase.
Treatment
The treatment for this condition is symptomatic and supportive as there has been no effective drug treatment so far. The aim of this treatment is to manage and alleviate individual symptoms and provide support for the patients and their families.
Disclaimer: The information provided here is for educational purposes only and should not be taken as medical advice. Always consult with a qualified healthcare professional for diagnosis and treatment. Information sourced from reliable medical databases.