Genetic basis of Centronuclear Myopathy in Great Danes - is caused by a mutation in the BIN1 gene (Bridging Integrator 1). This mutation is a single base change affecting the BIN1 gene, which is involved in muscle cell structure and function. The disease is inherited in an autosomal recessive manner, meaning affected dogs have two copies of the mutated gene while carriers have one copy and appear normal but can pass the mutation on.
Pathophysiology - The BIN1 gene mutation disrupts muscle fiber architecture, leading to progressive muscle wasting and weakness. Affected muscles show specific cytoarchitectural changes with central zones and abnormalities in muscle fiber structure. Clinical signs start around 6-8 months of age, with progressive muscle atrophy, exercise intolerance, muscle tremors, and collapse.
Complications - Onset typically occurs in puppies or young adults. Symptoms include exercise intolerance, muscle tremors, reluctance to move, progressive muscle wasting, especially in pelvic limbs. The disease progresses with increasing muscle weakness and collapse. Most affected dogs have a poor prognosis, and there is no effective treatment available. Many affected dogs are euthanized due to deterioration.
Why This Matters to Breeders and Vets - Genetic testing is available for the BIN1 mutation, enabling identification of carriers and affected dogs. Responsible breeding using genetic test results can prevent producing affected puppies. Understanding this disorder helps veterinarians diagnose the condition early and differentiate it from other neuromuscular diseases.
Summary - Centronuclear Myopathy in Great Danes is a severe, autosomal recessive inherited muscle disease caused by a mutation in the BIN1 gene. It leads to progressive muscle weakness and exercise intolerance beginning around 6 months of age. Genetic testing enables diagnosis and supports breeding strategies to reduce prevalence and prevent affected puppies.
