Inherited Myopathy of Great Danes is a rare inherited degenerative muscle disorder affecting Great Danes. Affected dogs typically have an onset of symptoms before one year of age. Symptoms most commonly include difficulties exercising, muscle wasting and tremors brought on by exercise. Dogs may also have an abnormal posture with the hind legs tucked under the body and the tail extended. Occasionally dogs exhibit difficulty breathing. Most dogs that present with symptoms develop a severe, rapidly progressive form of the disease and are euthanized between 1 to 2 years of age. However, it has been reported that some dogs may have a more mild form of the disease and may live into adulthood without significant progression of the symptoms.