Original PI relocated to another institution

The purpose of this study is to find out more about some of the unusual chemicals (called oligosaccharides) that can occur naturally as a result of processes in the body. Researchers want to look at how these chemicals change with time and how they change between different patients with MPSIVA. These unusual chemicals were recently discovered in the urine from patients with MPSIVA. The investigators would like to study these chemicals before a specific enzyme replacement therapy is used. If the investigators understand how these chemicals change, the investigators may be able to use them to monitor this condition in the near future as well as help doctors know whether certain therapies work well in their patients.

This is not a clinical trial and there is no outcome measurement. The biomarkers in this study are oligosaccharides that secreted in the urine from patients with MPSIVa. In this study, we will try to define the variability of these oligosaccharides in the same patient at different time points, including different month of a year and different collections during the day as well as variations of these oligosaccharide in different affected patients.

Inclusion Criteria:

• Diagnosis of Mucopolysaccharidosis IVA

Exclusion Criteria:

• Patients receiving enzyme replacement therapy.

Newly diagnosed or untreated Mucopolysaccharidosis IVA patients across the nation collected from national major genetic laboratories, national major genetic clinics, Includes the Emory Genetics Clinic, Mayo Clinic, UPMC, Children's Hospital of Philadelphia, and Nationwide Children's Center in Washington, DC.