Limb-girdle muscular dystrophy type 2D is an inherited genetic disorder that causes weakness and wasting of the muscles in the arms and legs.
The first sign of this disorder is often an unusual walking gait, such as waddling or walking on the balls of the feet, in addition to difficulty running. As the disorder progresses over time, affected individuals may require wheelchair assistance. Other symptoms of the 2D type of limb-girdle muscular dystrophy include scapular winging, in which the shoulder blades stick out from the back due to weak shoulder muscles, as well as overgrowth of the calf muscles (calf hypertrophy) and contractures of the Achilles tendon. The symptoms of this condition can vary greatly from person to person, even within the same family. Some individuals with the condition may experience only mild muscle weakness, while others may have severe symptoms that can be fatal. There is no cure or treatment for this disorder other than occupational and physical therapies to alleviate some of the symptoms.
This condition is caused by pathogenic (disease-causing) variants in the SGCA gene. Limb-girdle muscular dystrophy type 2D exhibits autosomal recessive inheritance, meaning both parents must be carriers to have a 25% chance of having a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. Carriers do not typically show any signs or symptoms of the condition. Other names for this condition include myopathic limb-girdle syndrome and alpha-sarcoglycanopathy.