uchenne muscular dystrophy (DMD) is the most common fatal genetic disease diagnosed in childhood. The disease almost always affect boys, and they tend to be diagnosed before the age of 5. Duchenne muscular dystrophy is classified as a rare disease. Children born with Duchenne muscular dystrophy have a fault, known as a mutation, on their dystrophin gene, the longest gene in the body. The fault means that they cannot produce dystrophin, a protein that is vital for muscle strength and function. This lack of dystrophin results in a progressive deterioration of muscle strength and function.