Duchenne Muscular Dystrophy

1. Genetic details: X-linked recessive disorder. Occurrence: 1 in 3,500 males

1.1. Common mating: normal male/carrier female. 50% of daughters would be carriers. 50% sons would be normal.

1.2. Common mating: Affected father/normal mother. All sons will be normal. All daughters will be heterozygous carriers.

2. Etiology: The muscle protein dystrophin controls the integrity of the muscle cells. The cells do not survive without this protein, which is missing in DMD.

2.1. This trait is more common in males because they only receive one copy of the disease from their mother.

3. Diagnostic testing: (1) SSQ (Sydney Swallow Questionnaire). (2) Radial bone mineral density

3.1. Radial bone density evaluation can prevent fractures and improve quality of life.

4. Common findings: Inability to walk by 10-12 years of age, gradual muscle degeneration, dysphasia.

5. Pathophysiology: disturbance of the heart and respiratory muscles. Death often happens due to respiratory or cardiac failure by 20 years of age.

6. Treatments: L-citrulline and Metformin

6.1. Can suspend loss of motor function and muscle decline