ABC Nightline: Darius Weems Incredible Cross-Country Journey

Darius Weems is on a mission, but even though he is only 23 years old, it's a race against time. Darius, an aspiring rapper and star of the documentary, "Darius Goes West," suffers from Duchenne Muscular Dystrophy, a rare genetic disorder that results in the disintegration of muscle tissue. Legs and arms are seized, and eventually, so are the muscles that surround the heart. In the United States, the majority of people afflicted with this disease die by age 25. Read more.

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