Autosomal recessive muscular dystrophy in Labrador retrievers

Autosomal recessive muscular dystrophy in Labrador retrievers was first rep orted in the mid-1970s. The method of inheritance follows a simple autosoma l recessive pattern, but age at onset and severity of clinical signs may va ry dramatically among affected littermates. A clinical diagnosis can be mad e from the history, signalment, and clinical signs, but a definitive diagno sis requires histopathologic evaluation of a muscle biopsy; histopathologic abnormalities typically occur as atrophy of type II muscle fibers. Althoug h there is no cure or definitive treatment for this condition, the prognosi s for animals with mild disease is favorable because clinical signs often s tabilize by 1 year. To date, there is no clinical test to identify carrier dogs. Known genetic carriers should not be used in breeding programs.