Mucopolysaccharidosis (MPS) VII (Brazilian terrier type) is an inherited Lysosomal Storage Disorder affecting dogs. Affected dogs have insufficient activity of the Enzyme beta-glucuronidase, which is responsible for breaking down glycosaminoglycans (GAGs). GAGs are an important component of Connective Tissue. In affected dogs there is an accumulation of breakdown products in cells causing abnormal growth and function of various different organ systems. Clinical signs of MPS VII (Brazilian terrier type) are most commonly associated with accumulations in the bones and joints. Therefore, affected dogs typically present between 1 to 4 weeks of age with symptoms of bone and joint disease. Affected puppies have disproportionally large heads with short muzzles, broad faces and domed skulls. Other skeletal deformities include joint laxity and deformed, crooked legs resulting in an inability to walk. Affected puppies are smaller than their normal littermates and exhibit a failure to thrive. Affected dogs die on their own or are euthanized within the first 5 weeks of life.