Multiple sulfatase deficiency


Multiple sulfatase deficiency is a very rare autosomal recessive lysosomal storage disease caused by a deficiency in multiple sulfatase enzymes, or in formylglycine-generating enzyme, which activates sulfatases. It is similar to mucopolysaccharidosis.

Signs and symptoms

Symptoms of this disorder commonly appear between one and two years of age. Symptoms include mildly coarsened facial features, deafness, ichthyosis and an enlarged liver and spleen. Abnormalities of the skeleton, such as a curving of the spine and breast bone may occur. The skin of individuals afflicted with this disorder, is typically dry. Children affected by this disorder develop more slowly than normal and may display delayed speech and walking skills.
The disease is fatal, with symptoms that include neurological damage and severe mental retardation. These sulfatase enzymes are responsible for breaking down and recycling complex sulfate-containing sugars from lipids and mucopolysaccharides within the lysosome. The accumulation of lipids and mucopolysaccharides inside the lysosome results in symptoms associated with this disorder. Worldwide, forty cases of Multiple Sulfatase Deficiency have been reported to date.

Causes

Multiple sulfatase deficiency is thought to be caused by any mutation of the SUMF1 gene which would render its protein product, the formylglycine-generating enzyme, defective. These mutations result in inactive forms of FGE. This enzyme is required for posttranslational modification of a cysteine residue in the sulfatase enzyme active site into formylglycine, which is required for its proper function.

Genetics

MSD has an autosomal recessive inheritance pattern.
The inheritance probabilities per birth are as follows:

Treatment