A woman who smelled a change in her husband six years before he was diagnosed with Parkinson's has inspired scientists to consider a new way of detecting the disease.
Scottish woman Joy Milne noticed something had changed with her late husband years before he was diagnosed with Parkinson's.
"His smell changed and it seemed difficult to describe, it wasn't all of a sudden, I got an occasional sort of [whiff] of this smell."
Joy Milne only linked the scent to Parkinson's after joining the charity Parkinson's UK and meeting people with the same distinct smell.
By chance, she mentioned this to a scientist at the end of a talk.
That scientist, Tilo Kunath, a Parkinson's UK fellow at the school of biological sciences at Edinburgh University, told Morning Report he was initially startled at the suggestion.
"She asked, 'do Parkinson's patients smell different?' I was taken aback ... but a long series of events led us to test her and she was extremely accurate. She could tell us from just t-shirts that were worn by patients and control individuals who had Parkinson's and who did not. We were very surprised to find that out."
Joy Milne has since identified the disease in six other people.
Mr Kunath said Mrs Milne possessed a unique ability to detect small changes in smell that the average person could not.
"She does describe it as slightly musky, sometimes woody but I was amazed watching her work that she could discriminate ... smells to me that would be the same, she would tell me what the differences were between these two odours. "
Mr Kunath said the change in odour occurred many years before a traditional diagnosis could detect Parkinson's.
"She can detect it in people that are in the mid-stages of Parkinson's. Her husband, she detected the change years before the serious symptoms started. We have one other example that she has been able to detect another individual eight months before he was diagnosed with his condition. It's certainly something that she can detect before the more serious motor symptoms occur."
He said while scientists did not really know why the smell changed in people who had Parkinson's, the discovery could be put into practical use.
"There's an ability to train dogs to detect different odours and different conditions."
"We hope to find a test to define the molecular signature on the skin on an individual with Parkinson's, well before or early stages of their condition."
He said early detection could also be used to identify individuals for clinical trials to give them experimental preventative medicines, that would prevent the more serious onset of Parkinson's.
"Joy's explained to us that the odour changes when the conditions worsening or if the medication isn't tuned properly so it could also be a way of monitoring the condition as making sure that the best treatment is being given."
Joy's husband Les was 45 when he was diagnosed with Parkinson's 20 years ago - he died in June this year.