Bovine mucopolysaccharidosis type IIIB

Area of Science:

• Veterinary Genetics
• Animal Disease Research
• Lysosomal Storage Disorders

Background:

• Mucopolysaccharidosis IIIB (MPS IIIB) is a rare, inherited metabolic disorder affecting cattle.
• It is characterized by the accumulation of heparan sulfate due to deficient alpha-N-acetylglucosaminidase (NAGLU) enzyme activity.
• Clinical signs manifest as progressive ataxia and gait abnormalities, typically appearing around two years of age.

Purpose of the Study:

• To report the discovery and genetic basis of MPS IIIB in cattle.
• To identify the specific mutation responsible for the disorder in affected animals.
• To provide a basis for genetic screening and disease eradication strategies.

Main Methods:

• Clinical observation and neurological examination of affected cattle.
• Genetic analysis to identify mutations in the NAGLU gene.
• Genotyping of affected bulls to determine the specific mutation.

Main Results:

• Cattle with MPS IIIB were identified with progressive ataxia and impaired mobility.
• A specific missense mutation, E452K (c.1354G > A), in the NAGLU gene was identified in affected bulls.
• Affected bulls were homozygous for this identified mutation.

Conclusions:

• The E452K mutation in the NAGLU gene is causative for MPS IIIB in cattle.
• Mutational analysis enables the identification of carriers and affected individuals.
• Genetic screening can be implemented to eradicate this mutation from cattle breeding populations, preventing the transmission of MPS IIIB.