What causes Duchenne Muscular Dystrophy? Duchenne is a genetic condition caused by a change in the gene that makes dystrophin. Dystrophin is a vital protein found in every muscle in the body. It acts like a shock absorber, protecting muscles as they contract and relax during everyday movement. When dystrophin is missing, muscles become fragile. Normal daily activity can cause tiny tears in the muscle cells. Without dystrophin, those tears can’t be repaired. These micro-injuries allow calcium to