The former British and Irish Lion, who earned 61 caps for Scotland, will now join forces with researchers at the University of Edinburgh to help them tackle the illness.
He made the announcement while on holiday with his family in New Zealand, ahead of Global MND Awareness Day.
Weir, is originally from Edinburgh and started playing rugby at Stewart’s Melville before moving to Melrose team in the Borders, where he is still based.
The 46-year-old, joins a host of sports stars including former Rangers footballer Fernando Ricksen who have been struck down by MND, which leads to paralysis and difficulties with speech, swallowing and breathing. Former Celtic star Jimmy Johnstone died from the illness in 2006 and the ice-bucket challenge started in the US after baseball player Pete Frates was diagnosed with the condition.
South Africa’s Joost Van Der Westhuizen, a former opponent of Weir’s in the 1990s also had MND and passed away in 2017.
Van Der Westhuizen visited the Euan MacDonald Centre Centre, a Scotland-wide research initiative based at the University of Edinburgh in 2013 to share knowledge and expertise. This is where Weir has pledged to support the researchers in their quest to better understand the disease, in the hope that it will eventually lead to new therapies. The Centre was set up in 2007 by Donald macDonald, a leading Scottish businessman and his son Euan, who was diagnosed with MND in 2003.
The disease also claimed the life of former Scottish Labour adviser Gordon Aikman earlier this year, aged 31.
Doddie Weir said: “Over the past few months a number of friends and family have raised concerns surrounding my health. I think then, that on this day set to help raise awareness of the condition, I should confirm that I too have Motor Neurone Disease. I should like to take this opportunity to thank the National Health Service in recognising then diagnosing this, as yet, incurable disease.”
He added: “I am currently on holiday in New Zealand with Kathy and the boys and when we return, I will devote my time towards assisting research and raising awareness and funds to help support fellow sufferers.
“There are plans in place to create a charitable foundation to help in any way we can and we will share these details with you after our family trip.”
Former Scotland rugby team-mate Gregor Townsend tweeted his support: “We are all with you Doddie. You will see some incredible support and love from the world of rugby. Gregor.”
At present there are no therapies that can stop the progression of MND, also known as amyotrophic lateral sclerosis (ALS) or Lou Gehrig’s Disease after a US baseball player and little is known about why it strikes some but not others.
Professor Siddharthan Chandran, Director of the Euan MacDonald Centre for Motor Neurone Disease Research, said: “We are immensely grateful to Doddie for his support at this difficult time for him and his family.
“Working in partnership with other researchers and charities such as MND Scotland, our goal is to bring forward the day when there are effective treatments for this very tough condition.”