Mucopolysaccharidosis IIIA (Sanfilippo syndrome) in a New Zealand Huntaway dog with ataxia.

Aim: To investigate the nature of a progressive ataxia in a New Zealand Huntaway dog.

Methods: The affected dog was examined clinically before being humanely killed and necropsied. Selected tissues were submitted to light and electron microscopy and to biochemical analyses.

Results: The histological lesions were interpreted as indicative of one of the forms of mucopolysaccharidosis type-III (MPS-III), a lysosomal storage disease. Biochemically there was a deficiency of heparan sulphamidase. All the heparan sulphate chains had non-reducing-end glucosamine-N-sulphate residues.

Conclusion: The disease is MPS-IIIA (Sanfilippo syndrome). An autosomal recessive mode of inheritance can be provisionally assumed from the nature of this disease in other species.