What is it?
MPS II is a rare disorder in which complex sugar molecules build up in many parts of the body. Individuals with MPS II usually have developmental disabilities, a distinctive facial appearance, and significant health issues. Without treatment, children with the severe form of MPS II do not survive.
Gene and enzyme function:
Mutations in the IDS gene cause MPS II. The IDS gene normally instructs the body to make iduronate 2-sulfatase, an enzyme that breaks down large sugar molecules known as glycosaminoglycans (GAGs). In people with MPS II, GAGs accumulate in the liver, spleen, heart, skeleton, skin, lungs, and brain, resulting in disease symptoms.
More information about symptoms:
People with the more severe form of MPS II are usually diagnosed during infancy. They have distinctive “coarse” facial features, a narrowed airway, enlarged livers and spleens, umbilical or inguinal hernias, short stature, a particular skin rash, and bone disease. They may also have reduced vision, hearing loss, lung disease, heart disease, developmental disability, and behavioral disturbances. People with the less severe form of MPS II may have a slower disease progression.
How common is MPS II?
MPS II is a very rare disorder, estimated to affect 1:100,000 – 170,000 males.
How is MPS II inherited?
MPS II is inherited in an X-linked recessive inheritance pattern.
Is there treatment?
This information is current as of November 2020. Decisions about if, when, and how to manage this condition should always be made in conjunction with your health care provider.
There is an FDA-approved enzyme replacement therapy that improves some of the symptoms of MPS II, but does not treat the neurologic features.
Click HERE for more information about MPS II treatment
Click HERE to see clinical trials studying an investigational enzyme replacement therapy and an investigational gene therapy for MPSII.
Additional information and support
Genetics Home Reference (GHR) and MedlinePlus