Mucopolysaccharidoses, which are also known as mucopolysaccharide storage (MPS) diseases, are a group of rare genetic disorders caused by the deficiency of one of ten specific lysosomal enzymes. The lysosomes are particles bound in membranes within cells that break down certain fats and carbohydrates (mucopolysaccharides) into simpler molecules. The accumulation of these large, undegraded mucopolysaccharides in the cells of the body causes a number of physical symptoms and abnormalities.
Sly syndrome (MPS-VII) is an MPS storage disease caused by a deficiency of the enzyme beta-glucuronidase that leads to an accumulation of dermatan sulfate (DS), heparan sulfate (HS) and chondroitin sulfate (CS) in many tissues and organs of the body including the central nervous system.
The clinical features of Sly syndrome vary from patient to patient, but all have short stature due to growth retardation, changes in bones visible on X-rays and some degree of mental retardation. Survival into adulthood is common with milder cases and osteoarthritis is a common complication.
The symptoms of Sly Syndrome are similar to those of Hurler Syndrome (MPS I) and the other Mucopolysaccharidoses. Symptoms may include mental retardation, short stature with an unusually short trunk, and/or abnormalities of the intestines, corneas of the eyes, and/or the skeletal system. Sly Syndrome is inherited as an autosomal recessive genetic trait.
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