Duchenne muscular dystrophy (DMD) is caused by a genetic mutation in the gene that provides instructions for making dystrophin, a crucial protein protecting muscle fibers. This protein's absence leads to muscle cell fragility and degeneration.
Understanding the Genetic Basis of DMD
- Gene Mutation: The primary cause is a mutation on the X chromosome. This means it's predominantly inherited from the mother, affecting primarily males. Multiple sources confirm this, including Cleveland Clinic, Johns Hopkins Medicine, and MDA.
- Dystrophin Deficiency: The mutated gene fails to produce functional dystrophin. Without this protein, muscle cells are vulnerable and progressively break down (Muscular Dystrophy Association, Pfizer). This is consistently reported across multiple reputable sources.
- X-Linked Inheritance: The location of the affected gene on the X chromosome explains the higher incidence in males, as females typically have a second, healthy X chromosome to compensate (MDA).
Impact of Dystrophin Deficiency
The lack of dystrophin results in:
- Muscle Weakness: Progressive muscle weakness and degeneration are hallmark symptoms.
- Muscle Degeneration: Muscle fibers become increasingly fragile and prone to damage.
- Loss of Muscle Function: This leads to a decline in motor skills and physical capabilities.
Multiple sources, including Rare Diseases, MedlinePlus, and Nature Reviews Disease Primers emphasize the role of dystrophin deficiency in the progression of DMD.
