From 
The AP:
For RJ Mitte, playing Walter White Jr. in AMC's "Breaking Bad" was art imitating life.
Like the 22-year-old actor, his character had cerebral palsy — just a 
more severe case, requiring Mitte to learn to walk on crutches and slow 
his speech for the role. Mitte says he also had to revisit some of the 
challenges he faced growing up, which served as "a great reminder" that 
helped him win the part.
"The past does haunt you, but it haunts you for a reason: to remind you 
of the mistakes and actions you've made along the way and you have to 
grow from those actions," he said.
Mitte says those experiences enabled him to bring something to the role that others couldn't.
"My disability has given me so many things that people will never 
understand unless you have it," he said in a recent interview. "Unless 
you've been through the physical therapy, unless you've been (through) 
the sweat, the tears, the family problems, the family struggles, but 
wondering how you're going to get that HMO, wondering how you're going 
to get those medical bills. You develop a different mentality and you 
develop a different look at how the world sees you and how you see the 
world."
Mitte isn't alone in winning roles that reflect his life: In his 
recently canceled sitcom, Michael J. Fox's title character had 
Parkinson's disease, as he does, and both "Glee" and "American Horror 
Story" feature actresses with Down syndrome.
Since the "Breaking Bad" finale, Mitte has played a wheelchair-bound 
character who suffered a spinal cord injury. He says other roles he's 
taken on include that of a young man with muscular dystrophy and another
 where he was "a bit mentally unstable."
"I'm not going to say that I don't get typecast from time to time but those are real characters," says Mitte. 
He says that while he realized there is "an opportunity to learn 
something from these characters," he just likes to have a good time with
 the roles, adding that "at the end of the day you have to have fun with
 it because this business is stressful enough not to enjoy what you do."