Becker Muscular Dystrophy (BMD): Causes, Symptoms & Information

Becker muscular dystrophy (BMD) is a genetic disorder that causes progressive muscle weakness and wasting. It is caused by mutations in the dystrophin gene, which provides instructions for making a protein called dystrophin. Dystrophin is essential for maintaining the structural integrity of muscle fibers. Without dystrophin, the muscle fibers become damaged and eventually die, leading to muscle weakness and wasting.

BMD is an X-linked recessive disorder, which means that it is more common in males than females. Males have one X chromosome and one Y chromosome, while females have two X chromosomes. For a male to have BMD, he must inherit a mutated dystrophin gene from his mother. Females can be carriers of the BMD gene, but they are usually not affected by the disorder.

BMD typically begins in childhood, with symptoms appearing between the ages of 5 and 15 years. The first symptoms are usually muscle weakness and wasting in the legs. The weakness gradually progresses to the arms, trunk, and neck muscles. As the muscles weaken, people with BMD may have difficulty walking, climbing stairs, and lifting objects. They may also experience fatigue and muscle pain.

There is no cure for BMD, but there are treatments that can help to slow the progression of the disorder and improve quality of life. Treatments include physical therapy, occupational therapy, bracing, and medication.

The prognosis for people with BMD varies. Some people may have a relatively mild form of the disorder and live a relatively normal life. Others may experience more severe symptoms and require a wheelchair or other assistive devices. The average life expectancy for people with BMD is about 40 years.