Transcript for Trevor Bayne Diagnosed with MS at 20
With that surprising diagnosis for one of nascar's brightest young stars. 22-year-old trevor baynes was the youngest driver to win the daytona 500. And has now revealed he has multiple sclerosis. Abc's john muller has the story. Reporter: His need for speed has propelled him to fame. At 20 years old, trevor bayne, became the youngest ever to win the daytona 500. But he's hit a bump in the road. Announcing he has been diagnosed with multiple sclerosis. In 2011, going to the mayo clin clinic, after being out of the race car with double-vision. Reporter: Bayne's little sister also has m.S., And was diagnosed this summer, after the double-vision and fatigue started affecting his driving. But the 22-year-old says his illness won't slow him down. I hope not. Our job is to go very fast. M.S. Can have a variable course. One person can have years where they're not affected much at all. Where someone else, the same age, presenting at the same time, can have a course that's rotten. Reporter: With the green light from doctors and nascar to keep racing, he'll compete in the sprint cup series and beyond. I've been racing since I was 5 years old. And this doesn't change a thing. I want to do what I've dreamed of. We have high hopes that we can continue to do that. Reporter: It's the same competitive experience that robin got to experience firsthand, when she challenged him to a go-kart race in 2011. I got two. Reporter: And while the challenge is more daunting, bayne says he is determined to switch gears and use his diagnosis as a way to help others. We get to focus on the race wins and everything else. It's something I want to be able to share with people. I know people can relate to struggles. Reporter: Confident it will be nothing more than a mere pit stop in life. For "good morning america," john muller, abc news, new york.
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