Researchers believe Parkinson's may alter a person's chemical signature, changing their odor.
Scientists from the Universities of Edinburgh and Manchester in the UK were inspired to launch the project after meeting 65-year-old British woman Joy Milne, whose husband died from Parkinson's disease in June of this year.
Mrs. Milne claims that 6 years before her husband Les was diagnosed with the condition, she noticed a change in his odor. "His smell changed and it seemed difficult to describe," she told BBC News. "It wasn't all of a sudden. It was very subtle - a musky smell."
After joining the charity Parkinson's UK, Mrs. Milne noticed she could pick up the same scent from other individuals who had Parkinson's - something she happened to mention to scientists.
As a result, Dr. Tilo Kunath, of the School of Biological Sciences at the University of Edinburgh - who will lead the new project - and colleagues conducted a pilot study to test Mrs. Milne's sense of smell, requesting her to smell worn t-shirts from six people with Parkinson's and six without the disease.
"We had them wear a t-shirt for a day then retrieved the t-shirts, bagged them and coded them. Her job was to tell us who had Parkinson's and who didn't," Dr. Kunath explained to BBC News.
Mrs. Milne correctly identified 11 out of the 12 participants, though the researchers note that she was adamant the final subject who she identified "incorrectly" did have Parkinson's. This participant was diagnosed with the disease 8 months later.
"So Joy wasn't correct for 11 out of 12, she was actually 12 out of 12 correct at that time," said Dr. Kunath. "That really impressed us and we had to dig further into this phenomenon."
New study could lead to a diagnostic test for Parkinson's
The researchers believe Parkinson's disease may trigger changes in the chemical signature of sebum - the oil secreted by the skin's sebaceous glands - which leads to a change in odor that can only be detected by individuals with a distinct sense of smell.
- The average age of Parkinson's onset in the US is 60
- Parkinson's was first described in 1817 by a British physician called James Parkinson
- Parkinson's is slightly more common in men than women.
To investigate their theory further, the team is embarking on a new study in which they will recruit around 200 individuals with and without Parkinson's.
The participants will be asked to complete a short questionnaire and will have skin swabs taken. These samples will be analyzed by the researchers with the aim of identifying molecules in the sebum that may be responsible for a change in odor among people with Parkinson's.
The skin swabs will also be assessed by Mrs. Milne and a number of smell experts from the food and drink industry.
Parkinson's disease is estimated to affect at least 500,000 people in the US, and more than 50,000 Americans are diagnosed with the condition every year.
At present, there is no test that can clearly diagnose Parkinson's, but Dr. Kunath and colleagues hope their new study will fuel such a development.
The video below provides further information on the project:
The team says a Parkinson's test could work in the same way as the devices used by airport security to identify traces of explosives; these work by emitting puffs of air in order to catch and analyze scent molecules from an individual's body.
Dr. Kunath adds:
"Our early results suggest that there may be a distinctive scent that is unique to people with Parkinson's. If we can identify the molecules responsible for this, it could help us develop ways of detecting and monitoring the condition."
As well as leading to the development of a diagnostic test for Parkinson's, Dr. Arthur Roach, director of research at Parkinson's UK, who is funding the new study, says the new project could even lead to a cure for disease.
"It's very early days in the research," he says, "but if it's proved there is a unique odor associated with Parkinson's, particularly early on in the condition, it could have a huge impact - not just on early diagnosis, but it would also make it a lot easier to identify people to test drugs that may have the potential to slow, or even stop Parkinson's, something no current drug can achieve."
Medical News Today recently reported on a study in which researchers identified a way to "melt" protein clumps called Lewy bodies in the brains of people with Parkinson's, which may lead to new treatments for the condition.