Dystrophin, DMD – Other Categories

The Dystrophin protein, encoded by the dystrophin gene, is part of the dystrophin glycoprotein complex which connects the inner cytoskeleton to the extracellular matrix in muscle fibres. This allows the muscle cell plasma membrane to remain structurally stable. Forms of inherited muscular dystrophy such as Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) result from mutations targeting the dystrophin gene. These disorders are X-linked, progressive and cause the gradually weakening of the muscles leading to respiratory failure and ultimately reduces the patient lifespan. In DMD, mutations lead to the production of premature stop codons and hence the truncated dystrophin protein product is vulnerable to nonsense mediated decay and degradation. Therefore dystrophin production in muscle cells is reduced. On the other hand, nonsense mutations which also contribute to DMD, cause exon skipping in BMD and result in an internally truncated protein product which are partially functional. The symptoms of BMD are later onset compared with DMD which develop in patients between 2 to 7 years.