When it comes to developing treatments and eventual cures for diseases, being able to diagnose a condition early and accurately makes a huge difference – and scientists have now developed a quick, reliable method of identifying people with Parkinson's disease.

The test can be run in as little as 3 minutes after a skin swab has been taken. The swab is analyzed for changes in the chemical mix of sebum, a natural waxy oil produced by the skin that has previously been linked to Parkinson's.

At the moment, there's no conclusive test for Parkinson's disease – specialists look at symptoms, medical history, the results of a lengthy physical examination, and in some cases, a brain scan to diagnose the condition.

"This test has the potential to massively improve the diagnosis and management of people with Parkinson's disease," says neurologist Monty Silverdale from the University of Manchester in the UK.

The new test builds on work done by researchers with Scottish woman Joy Milne, who has hereditary hyperosmia – a heightened sensitivity to smells.

After noticing her husband developing a more musky odor many years before he was officially diagnosed with Parkinson's, it was discovered that Milne could smell the signs of the disease on people.

That led the team to sebum, which is linked to the endocrine system, and keeps skin moisturized. Back in 2019, some of the same researchers identified how the chemical mix of sebum changed in an individual once Parkinson's disease was present.

Now we have a test based on that shift in biomarkers. Swabs taken in a clinic are sent off to a lab, where they undergo a mass spectrometry analysis to see their molecular make-up. For the purposes of the current study, samples from 79 people with Parkinson's were compared against samples from 71 people without the disease.

Joy Milne involved in Parkinson's research
Joy Milne helping with the research. (University of Manchester)

"When we do this, we find more than 4,000 unique compounds of which 500 are different between people with Parkinson's disease compared to the control participants," says chemist Depanjan Sarkar from the University of Manchester.

That the test is non-invasive and so quick in terms of generating results are positive signs, though the scientists still need to show that they can scale up the procedure and get it working outside of laboratory conditions.

Further down the line, the researchers say that other diseases and conditions could be diagnosed through an analysis of sebum – though as yet it's not fully clear why the onset of Parkinson's should cause these changes in the production of the fluid.

Parkinson's is currently the fastest growing neurological disease there is, and that growth is set to continue. While scientists are working hard to find a cure, there are ways to slow it down and manage it – and that's where an early diagnosis can be so important.

"We are tremendously excited by these results which take us closer to making a diagnostic test for Parkinson's disease that could be used in clinic," says chemist Perdita Barran from the University of Manchester.

The research has been published in the Journal of the American Chemical Society.