Mucolipidosis IV is a rare genetic disorder passed
down from parents to children. Both parents must carry the recessive
gene for children to be affected. About 95% of people with Mucolipidosis
IV have the typical or severe strain. The remaining 5% are affected with a milder form of the disease. The condition affects transportation of fats and proteins causing these substances to build up in the body. Parents carrying the gene will not have any symptoms of Mucolipidosis IV.
Who is at Risk?
About 1 in 40,000 people are diagnosed with the disease. Of these cases, 70% are from an Ashkenazi Jewish decent.
Typical symptoms of Mucolipidosis IV affect movement, coordination, eye function and stomach function. Patients may present with:
- Reduced vision
- Blurry vision
- Complete vision loss
- Iron deficiency
Mucolipidosis IV is a degenerative disease. Symptoms are typically first noticed within the first year of life. Developmental delays, difficulty walking and loss of vision are the most common complications. Eventually, patients with typical Mucolipidosis IV will go blind. Early death occurs in most cases with lifespan reaching around 40 years.
Patients must inherit the disease from two recessive parents, but parents appear symptom free so a detailed family history is crucial to diagnosis. If family history includes one or more relatives with Mucolipidosis IV, genetic testing is performed to verify the disease.
Without a family history of the disease, patients may be diagnosed with cerebral palsy instead of Mucolipidosis IV. It is extremely important for patients of Ashkenazi Jewish decent to undergo genetic testing for Mucolipidosis IV if symptoms appear.
Three mutated genes have recently been discovered. Two of these genes are said to account for the majority of cases. The disease is rarely found outside of the Ashkenazi Jewish population.
There is no cure for this disease. Symptoms can be treated with medications, supplements and physical therapy. Iron deficiency, for instance, can be treated with iron supplements. Patients with progressive vision loss may be eligible for cornea replacement surgery, but this provides only temporary relief as the condition will eventually affect the donor cornea.
Patients with Mucolipidosis IV generally live a shortened lifespan. Patients may live into their 40s with regular treatment.