The type of Muscular Dystrophy that Doug has is known as Duchenne Muscular Dystrophy - or DMD. DMD is a genetic disorder caused by a mutation in the X chromosome. This mutation makes the body unable to produce the dystrophin protein. This deficiency, in turn causes muscle cells to die. These muscle cells are eventually replaced by fatty or connective tissue.
In a DMD patient like Doug, symptoms begin early - often by age 3 or 4. By the age of 10, many patients are unable to walk without leg braces. By the age of 12, most are confined to a wheelchair. The circulatory and respiratory systems also rely on muscle strength, and are not immune to the effects of DMD. The condition is terminal, usually before the age of 30. Doug is currently 6 years old.
DMD occurs in approximately 1 out of every 3,500 boys.
For more information, click "Read more" and follow the links.
Facts about DMD from MDUSA.
Facts from Wikipedia.
Facts from kidshealth.org
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