A team of researchers has identified the compounds produced by Parkinson's sufferers by using the sense of smell.
This is all thanks to an elderly Scottish woman with a special ability to literally sniff out Parkinson's disease.
To date, there have been no reliable tests to detect the presence of the disease, making early intervention and treatment difficult.
But 68-year-old Joy Milne, a retired nurse from Perth, has helped scientists develop a form of diagnosis.
UK Professor Perdita Barran explains that Milne first noticed the "musky" smell on her husband Les, who later became a Parkinson's sufferer himself.
30 years ago the woman's husband began to smell differently to her. 12 years later he was diagnosed with Parkinson's disease.
When the couple began attending group sessions with other people diagnosed with the diseased, Milne recognised the same smell she had detected many years prior.
After approaching researchers, Milne helped them develop a test that could detect the smell of the molecules.
Professor Barran and her team devised a T-shirt sniffing test for Milne who accurately identified all affected patients.
Scientists then simulated the woman's nose to using mass spectrometry to find the compounds that are biomarkers for Parkinson's disease.
The professor explains that the development will help identify at-risk patients and could improve early diagnosis of the disease to prevent the debilitating symptoms.
Joy Milne is granny from Perth in Scotland. She used to be a nurse and has a good sense of smell.— Perdita Barran, Professor of Mass Spectrometry - The University of Manchester
She's also synesthetic, which means she associates colours with smells. This helps her to identify things.— Perdita Barran, Professor of Mass Spectrometry - The University of Manchester
She was able to detect the disease by this smell before the motor symptoms set in.— Perdita Barran, Professor of Mass Spectrometry - The University of Manchester
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