Limb-girdle muscular dystrophy type 2E (LGMD2E), also known as beta-sarcoglycanopathy is a muscle-weakening condition resulting from a deficiency or abnormality in the beta-sarcoglycan protein.
Symptoms of this disorder exhibit significant variation among individuals, even within the same family, ranging from mild muscle weakness to severe and potentially life-threatening manifestations. Typically, LGMD2E manifests in childhood, primarily affecting proximal muscles like those in the hips, shoulders, and abdomen, as well as muscles in the thighs and upper arms. The progression of muscle weakness varies, often necessitating wheelchair use due to severe weakness. Additional symptoms include calf hypertrophy (overgrowth), contractures, scapular winging of shoulders, scoliosis (curved spine), and the possibility of respiratory and heart complications, although it does not impact cognitive function.
LGMD2R is caused by pathogenic (disease-causing) variants in the SGCB gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background.
Resources:
Muscular Dystrophy Association
Revised September 2023