Scientists at the University of Manchester have discovered small molecules contained in sebum – a substance secreted by the skin – that are responsible for a unique scent in people with Parkinson’s disease. The research comes after Joy Milne, a retired nurse from Scotland, discovered she could detect the disease through smell. Joy realised people with Parkinson’s disease had a distinct and different smell, which changed intensity as the condition progressed. She first noticed her husband Les had developed a ‘musky’ smell six years before he was diagnosed with Parkinson’s disease, and years before he had developed any motor symptoms.
Scientists already knew the disease could cause excessive production of sebum, and inspired by Joy’s ability to detect the disease through smell decided to conduct further research.
Through their research, scientists at the University of Manchester’s Institute of Biotechnology (MIB) were able to identify the molecular compounds that give the condition its unique odour.
To figure out what makes the smell, at a molecular level, the ream analysed “volatile components” from the sebum of people with the disease. The odour was then double checked by Joy.
The researchers collected sebum samples from the upper backs of more than 60 participants, both with and without Parkinson’s.
After analysing the sample data, they found the presence of hippuric acid, eicosane and octadecanal, which they say “indicates the altered levels of neurotransmitters found in Parkinson’s patients, along with several other biomarkers for the condition”.
By considering the levels of these molecules found in the test samples, the team has generated a model that can now identify and diagnose Parkinson’s at all stages of the condition.
The results could lead to the development of an early diagnosis test for the disease.
At present, there are no tests which can conclusively show if a patient has Parkinson’s disease – doctors diagnose the condition based on symptoms, medical history and a detailed physical examination, according to the NHS.
“Now we have proved the molecular basis for the unique odour associated with Parkinson’s we want to develop this into a test,” said Perdita Barran, Professor of Mass Spectrometry at MIB.
“This could have a huge impact not only for earlier and conclusive diagnosis but also help patients monitor the effect of therapy.
“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.”
Professor David Dexter, deputy director of Research at Parkinson’s UK, said: “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.
“More research is needed to find out at what stage a skin test could detect Parkinson’s, or whether it also occurs in other Parkinson’s related disorders, but the results so far hold real potential – both to change the way we diagnose the condition and it may even help in the development of new and better treatments for the 145,000 people living with Parkinson’s in the UK.”
“We acknowledge this is a small study but it does open the door to the development of a non-invasive screening test for Parkinson’s, potentially leading to earlier detection for thousands of patients,” added Dr Monty Silverdale, consultant neurologist and honorary senior lecturer in Neuroscience at the University of Manchester.
Parkinson’s disease is a condition in which parts of the brain become progressively damaged over many years.
There is currently no cure for the disease, but treatments are available to help control symptoms.
The three main symptoms affect physical movement and include tremors, slowness of movement and muscle stiffness.