Sebum is an oily secretion from sebaceous glands under the skin which are connected to the endocrine system. The scientists have found that sebum can be used as a diagnostic biofluid, which is rich in hydrophobic endogenous metabolites.

Altered sebum production is a well-recognised feature of Parkinson’s. The sampling procedure they have developed is simple and non-invasive; sebum is collected in clinics from the upper back of patients and posted in the regular mail 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 4000 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 exciting 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 this research led by the University of Manchester, which has studied the sebum from people with and without Parkinson’s. Our work is on-going, and our trial has now recruited over 2000 patients.