Mucopolysaccharidosis type VI (MPS 6)

Mucopolysaccharidoses are a group of hereditary metabolic disorders and part of the lysosomal storage disease family. In the breed Miniature Pinscher, Mucopolysaccharidosis Type 6 (MPS 6) is caused by deficiency of the enzyme arylsulfatase B (ARSB). MPS 6 is inherited in an autosomal recessive manner. Affected dogs show early onset of corneal cloudiness, systemic skeletal deformities (facial dysmorphia, kyphosis, limb abnormalities) and stunted growth. Urinary analysis emerges excessive amounts of excreted dermatan and chondroitin sulfate as well as a strongly positive urinary toluidine blue MPS spot test. The serum ARSB activities are nearly absent. In the breed Miniature Pinscher, the underlying genetic variant seems to have a relatively high allele frequency. Affected dogs require intense nursing care and often have to be euthanised as puppies or young adult dogs because of the worsening clinical signs.