Parkinson’s is a devastating disease that affects millions of people all over the world. Now, a woman with a keen sense of smell is helping doctors to make major advances in early detection of the disease.

Joy Milne is a 68 year-old retired nurse from Perth, Scotland who possesses the uncanny ability to smell Parkinson’s on other people. Describing the smell as a “musky, oily odor,” Joy first smelled it on her husband decades ago. Twelve years later, he was diagnosed with Parkinson’s at the age of 45.

Joy had no idea that she had been smelling the disease for decades until she went to a support group for Parkinson’s patients and detected the odor on everyone there. She decided to mention this to Parkinson’s experts, and they have since been working with Joy directly to find ways to detect the disease earlier.

To test out Joy’s abilities, experts gave her dozens of shirts, some of which were worn by Parkinson’s sufferers and others worn by people who don’t have the disease. Incredibly, Joy was 98 percent correct in picking which shirts were worn by Parkinson’s sufferers.

Scientists have since found that Joy is smelling a compound contained in the patients’ sebum, a waxy, lipid-based biofluid which moisturizes and protects the skin, particularly on the forehead and upper back. Those who have Parkinson’s produce an excessive amount of sebum, and Joy possesses the ability to smell it.

Thanks to Joy’s nose, scientists have been able to identify specific biomarkers in the sebum that serve as red flags for the disease, which will help them detect it earlier.

“Finding changes in the oils of the skin in Parkinson’s is an exciting discovery that was sparked by a simple conversation between a member of the public and a researcher,” explained Professor David Dexter, Deputy Director of Research at Parkinson’s UK.

“More research is needed to find out at what stage a skin test could detect Parkinson’s, or whether it is also occurs in other Parkinson’s related disorders, but the results so far hold real potential,” he added. “Both to change the way we diagnose the condition and it may even help in the development of new and better treatments for the 145,00 people living with Parkinson’s in the UK.”

Early detection is crucial for Parkinson’s because it may help scientists come up with better treatment options. Experts are incredibly grateful to Joy for all that she has given them.

“This could have a huge impact not only for earlier and conclusive diagnosis but also help patients monitor the effect of therapy,” says University of Manchester Professor Perdita Barran, one of the study’s lead researchers. “We hope to apply this to at risk patient groups to see if we can diagnose pre-motor symptoms, and assist with potential early treatment.”

Find out more about this in the video below.