A new method to detect Parkinson’s disease uses skin swabs to analyse sebum has been developed, in a test which can take as little as three minutes.
A new study uses mass spectrometry to analyse sebum, and found that lipids of high molecular weight that are substantially more active in people living with Parkinson’s.
The breakthrough stems from the observation of Joy Milne, who discovered that she can distinguish Parkinson’s in individuals from a distinct body odour before clinical symptoms occur.
Joy first detected the odour on her husband Les, who was diagnosed with Parkinson’s at the age of 45. She only linked the odour to the disease after Les was diagnosed and they met people at a Parkinson’s UK support group who had the same distinctive smell.
Joy has hereditary hyperosmia – a heightened sensitivity to smells – which has been exploited to find that Parkinson’s has a distinct odour which is strongest where sebum collects on patient’s backs and is less often washed away.
Building on this, researchers from The University of Manchester used cotton swabs to sample people and identify the compounds present with mass spectrometry. The method developed involves paper spray ionisation mass spectrometry combined with ion mobility separation and can be performed in as little as three minutes from swab to results.
Professor Perdita Barran, who led the research, said: “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.”
Altered sebum production is a well-recognised feature of Parkinson’s. The new sampling procedure is simple and non-invasive; sebum is collected in clinics from the upper back of patients and posted to the lab.
Describing the new technique, Dr Depanjan Sarkar said: “The sebum is transferred to filter paper from sampling swab, and we then cut this to a triangle, add a drop of solvent, apply a voltage and this transfers compounds from the sebum into the mass spectrometer.
“When we do this, we find more than 4,000 unique compounds of which 500 are different between people with PD compared to the control participants.”
The Manchester team now see this as a major step forward towards a clinical method for confirmatory diagnosis of Parkinson’s, for which to date there is no diagnostic test based on biomarkers.
Professor Monty Silverdale, clinical lead on this study, said: “This test has the potential to massively improve the diagnosis and management of people with Parkinson’s disease.”
The current and future focus is to translate these findings into a test of clinical utility. This new work also opens the door to possibly diagnosing other diseases through non-invasive sebum analysis and the team, along with the University of Manchester, have launched a spin out company Sebomix Ltd. to develop this further.
The charities Parkinson’s UK and the Michael J. Fox Foundation as well as the Royal Society funded the research.
