Duchenne Muscular Dystrophy

What is Duchenne Muscular Dystrophy?

Duchenne muscular dystrophy (DMD) is a genetic disorder that leads to muscle degeneration and weakness. It is one of nine types of muscular dystrophy. DMD primarily affects the skeletal muscles, which control movement, though it can also impact the heart and other organs.

As DMD progresses, affected individuals usually face difficulty in walking, experience frequent falls, and may ultimately need a wheelchair for mobility. The disorder can further complicate the respiratory and cardiovascular systems, leading to life-threatening conditions.

Who Does DMD Affect?

DMD predominantly affects boys, though rare cases in girls have been documented. Here’s a breakdown of its demographic reach:

Gender: About 1 in 3,500 to 5,000 male infants worldwide is born with DMD. Females can be carriers of the disease but usually exhibit milder symptoms or remain asymptomatic.
Age: Symptoms typically begin between ages 2 and 3. By the age of 12, many affected children might be wheelchair-bound due to the progression of muscle weakness.
Ethnicity: DMD knows no ethnic bounds and impacts individuals of all racial and ethnic backgrounds.

How Does Someone Get DMD?

Duchenne muscular dystrophy is inherited in an X-linked recessive pattern. Here’s how it works:

Genetic Mutation: DMD is caused by a mutation in the DMD gene located on the X chromosome. This gene is responsible for the production of a protein called dystrophin, crucial for muscle fibre stability. Mutations in this gene lead to the absence or decreased production of dystrophin, causing muscle cells to be damaged and die over time.
Carriers: Females have two X chromosomes, while males have one X and one Y chromosome. A male inherits the X chromosome from his mother and the Y chromosome from his father. If a mother is a carrier of the DMD gene mutation, she has a 50% chance of passing it on to her son, leading to DMD.
Spontaneous Mutation: In some cases, DMD can occur without any known family history due to spontaneous mutations in the individual’s gene.

Treatment Options

Currently, there is no cure for DMD. However, treatments aim to control symptoms, enhance quality of life, and slow the progression of the disease. Here’s an overview of the treatment landscape:

Medication:
- Corticosteroids: Drugs like prednisone can help improve muscle strength and delay the progression of certain symptoms. However, long-term use can have side effects.
- Heart Medications: As DMD can affect the heart, medications like angiotensin-converting enzyme (ACE) inhibitors or beta-blockers might be prescribed to address cardiac issues.
Therapy:
- Physical Therapy: Regular physical therapy can help maintain muscle strength, flexibility, and function.
- Respiratory Therapy: As the diaphragm and chest muscles weaken, respiratory therapy becomes essential. Devices to assist night-time breathing might be recommended.
Surgical and Other Procedures:
- Mobility Aids: Braces, walkers, and wheelchairs can help with mobility and posture.
- Breathing Assistance: Mechanical breathing assistance might be needed, especially during the night.
- Cardiac Procedures: Cardiac problems associated with DMD might necessitate surgical interventions in some cases.
Emerging Treatments:
- Gene Therapy: Research is ongoing to develop techniques to replace the defective DMD gene or correct its mutations.
- Exon Skipping: This technique targets the genetic instructions cells use to make dystrophin, aiming to produce a slightly shorter but still functional version of the protein.

It’s essential for individuals diagnosed with DMD and their families to work closely with a multidisciplinary medical team. This ensures a holistic approach to manage the varied and complex challenges posed by the disorder. As research continues, there is hope that more effective treatments, and potentially a cure, will be found in the future.

Learn more at defeatduchenne.ca.