Description:  Myotubular myopathy 1 is an inherited muscle disease that also affects dogs. Affected puppies are usually normal at birth, but at the age of 7 to 13 weeks, they begin to show muscle weakness, decreased muscle mass, and exercise intolerance. Affected puppies have a problem standing up and keeping their heads up. The disease progresses rapidly, from general muscle weakness and frequent episodes of collapse to complete inability to stand. Alternatively, the inability to raise the head usually within 4 weeks of the initial signs. Dogs that are able to stand have an arched back and neck and a stiff gait. While the disease is not painful, affected dogs are often euthanased at 3 to 4 months of age due to rapid and severe disease progression.

Myotubular myopathy 1 is inherited in dogs in a recessive manner linked to the X chromosome, which means that female dogs must inherit two copies of the mutated gene (one from each parent) in order to develop the disease, while males only need one copy of the mutated gene from the mother, to develop the disease. Therefore, male dogs are more likely to show symptoms of the disease. Every male pup that is born to a bitch known to carry myotubular myopathy 1 (Rottweiler type) has a 50% chance of inheriting the disease.

Inheritance: X-Linked Recessive

Mutation: c.1151A > C, p.(Q384P) in MTM1 gene, chrX:118901282 (canFam3): A/C

Sample: EDTA whole blood (1.0 ml) or 2 buccal brushes

The analysis is suitable for the following breeds: Rottweiler

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