Limb-Girdle Muscular Dystrophy, Type 2B (DYSF)
Limb-girdle muscular dystrophy, type 2B is an autosomal recessive, pan-ethnic disorder that is caused by pathogenic variants in the gene DYSF. This form of muscular dystrophy presents with weakness of the pelvic and shoulder girdle, usually in late adolescence or early adulthood. Progression is slow and weakness does not always extend to the upper limbs. Patients are usually wheelchair-bound about 25 years after diagnosis, and life expectancy may be shorter than a natural life-span. Several other muscular dystrophies can be caused by pathogenic variants in DYSF, including a milder form known as Miyoshi muscular dystrophy, and a form that progresses more rapidly, known as distal myopathy with anterior tibial onset. Currently, it is not possible to predict the type and severity of DYSF-caused muscular dystrophy that a patient will develop based on the genotype.
For information about carrier frequency and residual risk, please see the residual risk table.