Limb-Girdle Muscular Dystrophy, Autosomal Dominant (LGMDD)

Limb girdle muscular dystrophy (LGMD) is a genetically inherited musculoskeletal disease characterized by progressive, predominantly proximal muscle weakness (Straub et al. 2018). Walton and Nattrass introduced the term in 1954 (Walton and Nattrass 1954). LGMD is a rare disease with an estimated incidence of 1 to 6:100,000 and a prevalence of 1:14,500 to 1:123,000 (Chu and Moran 2018). Today, more than 30 different subtypes of LGMD have been reported. LGMD subtypes are highly variable in the age of onset, disease progression, and severity. Several genes are involved in various types of LGMDs, and pathogenic genetic variants in each subtype can cause diseases with a variety in age of onset, disease progression, and involvement of joints, muscles, heart, and respiratory system. Therefore, the underlying mechanism of different types of LGMDs differs (Chu and Moran 2018; Taghizadeh et al. 2019). In the 229th ENMC workshop, held in March 2017, the classification and nomenclature of LGMD was updated. The autosomal dominant LGMDs was named as D and numbered from 1 to 5, and the recessive forms as R and numbered from 1 to 23 (Straub et al. 2018).