The 47-year-old hopes drugs will eventually be found to combat the condition, but admitted he and others with MND can only ponder their future.
He said: “There is frustration and that is with the lack of a solution - for the moment. But the apparent shortage of news or progress in finding new drugs to suppress the onset or fight the disease is frustrating - something I share with other sufferers.”
During a BBC interview Weir asked himself and his doctors if rugby could have been a contributing factor to the diagnosis:
“We have maybe 450 to 500 sufferers of MND in Scotland - and quite a large majority probably wouldn’t have played rugby.
“I don’t think there’s any connection to it at the moment but the reason behind that is that there’s maybe not a lot of studies put together, not a lot of work or focus put on MND at the moment in the world, so hopefully we can try and change that and try to find the solution.”
The 47-year-old former international announced his diagnosis in June to raise awareness of the degenerative condition, and promised to devote his time to helping with research and supporting fellow sufferers.
He recently launched the Doddie’5 Weir’s Discretionary Trust, which uses his former rugby shirt number in its name and aims to establish the My Name’5 Doddie Foundation.
He said: “I’m not too bad - probably quite well in terms of what the condition can do. I have some problems with my hands just now, so it can be quite tricky when doing a tie or some buttons on a shirt.
“I might be lucky it started with my hands. Other people it could be their voice or when they are eating, or legs. I can do most things - just a wee bit slower.
“But you have to remember I may have had this condition for maybe a couple of years. So I’m getting on not too bad; I can still walk, still talk, still drive the car, so not too bad. And hopefully that’ll be the same for quite a long time.”
During television interviews for BBC Scotland and Scottish Television, the one-time British and Irish Lions forward revealed he first had concerns after losing power in his left hand 18 months ago,
He first thought he had injured himself while farming, however, other symptoms made him think there could be a wider issue.
He said:”I noticed other wee changes. Maybe it wasn’t the right thing to do but I had a look online. When I read that, and saw what the condition meant, I realised I could be in a bit of trouble.”
One of the first places Weir sought counselling was with the J9 Foundation in South Africa, set up after World Cup winner Joost Van Der Westhuizen, who died in February, had been diagnosed with MND.
He added: “I’d met him at Murrayfield a few years back, when he was travelling to raise awareness about motor neurone disease, so his J9 Foundation was one of the first places I sought out information. There is a lot of detail to be had on the matter. Unfortunately, less-so a solution.