Joy Milne, a woman from Scotland, discovered she could smell Parkinson’s disease—years before symptoms appeared. She first noticed a musky odor on her husband Les in 1982, long before his diagnosis. At the time, she assumed it was due to his job in hospital operating rooms.

Years later, after Les was diagnosed, Joy realized the same distinct scent was present in others with Parkinson’s. After his death in 2015, she promised to use her rare gift to help others. “Les and I should’ve been enjoying retirement, but Parkinson’s stole our lives,” she said.

Joy began working with researchers, using her sense of smell to identify changes in skin oil, or sebum, linked to Parkinson’s. Her efforts inspired scientists at the University of Manchester to develop a skin swab test.

The new test analyzes sebum and is 95% accurate under lab conditions. Researchers hope to roll it out for NHS use within two years.

Joy believes early diagnosis could have changed everything: “We would have spent more time with family… It might have explained the mood swings and depression.”