Disease overview

Mucopolysaccharidoses (MPS) are a group of inherited metabolic diseases characterized by the improper degradation and accumulation of long chains of sugar molecules called glycosaminoglycans (GAG). This occurs as a result of the absence or malfunctioning of lysosomal enzymes, which have the important function of digesting and removing waste from the cells. The buildup of GAG in dogs causes abnormalities in the joints, bones, and other organs of the body.

Gene name

NAGLU

Inheritance

Autosomal recessive

Signs and symptoms

Signs vary widely between different forms of Mucopolysaccharidoses (MPS). Dogs with MPS are usually diagnosed between two and five months of age, though progressive symptoms are typically apparent in the first month of life. The most common symptoms can include slow growth, dwarfism, large head, weakness in the hind legs and/or deformed legs, unusually broad chest, corneal clouding and/or ocular lesions, and liver and/or heart complications. Signs of MPS IIIB typically present at around 2 years of age and slowly progress.

How is it diagnosed

A veterinarian will conduct a thorough exam, including a review of health history. Labwork and other diagnostics are needed to determine the causes of the wide range of symptoms associated with this disease. MPS may be suspected based on clinical signs, white blood cell granules, and a positive urine MPS spot test. Genetic testing can assist veterinarians with diagnosis and help breeders identify affected and carrier dogs.

Breeds at higher risk

Citations

Raj K, Ellinwood NM, Giger U. An exonic insertion in the NAGLU gene causing Mucopolysaccharidosis IIIB in Schipperke dogs. Sci Rep. 2020 Feb 21;10(1):3170. doi: 10.1038/s41598-020-60121-3. PMID: 32081995; PMCID: PMC7035321.

Disclaimer

Disease diagnosis and treatment should always be performed by a veterinarian. The following information is for educational purposes only.