If you thought your sense of smell was pretty good, meet Joy Milne of Perth, Scotland. Her nose really does know.

After her husband Les was diagnosed with Parkinson's disease, Joy noticed others at a charity event for Parkinson's had his same smell. She mentioned it to researchers, who wanted to find out whether she really could sniff out the disorder. Les died in 2015, but scientists have continued to delve into Joy's unique ability. That research may now lead to the first diagnostic test for the disease.

The scientific trail

Scientists at Manchester University tested Joy's sense of smell by asking her to sniff skin swabs taken from people who were already diagnosed with Parkinson's, as well as control subjects. She also smelled swabs from people who didn't have the disease, though scientists didn't tell her which swabs were which.

Milne was able to correctly identify the swabs that came from people with Parkinson's. She did a similar test with T-shirts at Edinburgh University and was again not only able to discern people with the disease, but correctly identify everyone in the test who didn't have the disease. The super-sniffer was also able to identify Parkinson's in someone who had not been diagnosed and didn't have any symptoms — but that person soon later was diagnosed.

Milne's unique capacity tipped researchers off that there were 10 "signature molecules" that may allow scientists to diagnose the disease before symptoms start.

"For all the serendipity, it was Joy and Les who were absolutely convinced that what she could smell would be something that could be used in a clinical context," Manchester University's Perdita Barran, told the Telegraph, "and so now we are beginning to do that."

Creating a diagnostic test

Other super-smellers like Joy say they can smell the distinct musky smell of Parkinson's, too. Their noses are helping the ongoing research by the Manchester team, which has pinpointed where those signature molecules are found: in the sebum or oily substance produced on your face and back. In fact, they've finally come up with a simple test, according to a study published in ASC Science.

Up to this point, there have been no tests for Parkinson's, and it's not until more than half of certain types of nerve cells in the brain have been destroyed that symptoms appear. With this new knowledge, the team is working with dogs, training them to smell for the molecules before symptoms begin, according to Discovery magazine.

Whatever diagnostic tests might be developed from what started with one woman's great nose could be a boon for those who will get Parkinson's. Earlier interventions could be helpful in improving quality of life for the 60,000 Americans diagnosed with the disease every year. Even more impactful could be identifying the disease in the thousands of cases in the United States that don't get diagnosed before people are suffering acutely — and that number stretches into the millions worldwide.

Editor's note: This story has been updated since it was originally published in December 2017.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Woman who can smell Parkinson's just put us one step closer to a test for the disease
Joy Milne's amazing ability is helping scientists develop a diagnostic test for the disease.