The 28-year-old Irish competitor won both T13 sprints at Beijing 2008 and London 2012 as well as at the last World Championships in Lyon, France in 2013, but the imminent arrival of his child means he has been forced to focus on just the shorter distance in Qatar's capital.

Smyth was reclassified from T13 to T12 last year due to the progression of his visual impairment, Stargardts disease, and will compete in that category in Doha.

He has just resumed racing following a long recovery from knee surgery in the early part of this year, and was recently crowned as the "fastest Paralympian on the planet" after he defeated fellow leading sprinters in a showcase race in Copacabana to mark the one year to go celebrations before the Rio 2016 Paralympics.

"My wife is actually due on October 25 so that’s probably the more important reason that I’m just doing the 100,” Smyth told RTÉ Sport.

“I actually arrive back home on the morning of the 25th so it’s going to be a bit close.

“It has been a tricky year and quite a long year.

“This year there is that aspect of having to take a step back in order to hopefully take two steps forward.

"That’s just something I had to do.

“It’s been difficult.

"Any athlete will tell you coming back from injury is difficult.

“My expectation is still to go there and win gold.”

Ireland have named a nine-strong team for the World Championships, with triple Paralympic gold medallist Michael McKillop, who won his medals in the T37 800m and 1500m, also selected for those races.

Also in the squad is London 2012 bronze medallist Orla Barry, who clinched the third step on the podium in the T57/58 discus. 

Three-time Paralympian and wheelchair racer at 100m and 400m John McCarthy joins the trio, as do Deirdre Mongan in the F53 shot put, Lorraine Regan in the F56 javelin, Noelle Lenihan in the F38 discus, Niamh McCarthy in the F41 discus and Hayley Fitzsimons in the F40 shot put.

The event in the Suhaim Bin Hamam Stadium will take place between October 22 and 31. 



Related stories
September 2015:  Smyth crowned world's fastest Paralympian with victory in race to mark One Year to Go until Rio 2016
September 2014: Ireland launches Rio 2016 Paralympic Games Volunteer Programme
August 2014: World and Paralympic champion Smyth completes double at IPC Athletics European Championships
August 2014: Peacock wins duel and Smyth brushes aside reclassification at start of IPC Athletics European Championships