Producer Stuart Blackburn said the 25-year-old star was discovered after the soap held a workshop for actors with disabilities, and he praised Bairstow's "lovely sense of timing", reported Daily Mirror.
"We ran a workshop for actors with disabilities. We recognise that they get so few auditions and we found Liam who was just brilliant.
"This isn't some politically correct thing. We've actually discovered a really great actor with a lovely sense of timing and the cast have been loving working with him," he said.