Researchers identify “unique smell” in search of early Parkinson’s disease diagnosis

Researchers have identified small molecules in a substance secreted by the skin that are responsible for a “unique scent” in people with Parkinson’s disease.

The astonishing discovery was made after Scottish academic, Joy Milne, was able to detect the disease on her husband purely by smell.

The 68-year-old from Perth said she first noticed a “musky” smell on her husband Les, who was later formally diagnosed with the rare condition.

This discovery inspired a team of scientists, from the University of Manchester, to set out to identify why people with Parkinson’s disease may smell the way they do.

According to the report, the researchers used mass spectrometry to identify the molecular compounds in Sebum, a waxy, lipid-based fluid that moisturises the skin. While it was already known that Parkinson’s disease causes rapid additional production of sebum, it was not known why the smell of the fluid was changing.

A number of sebum samples were collected from subjects, both with and without Parkinson’s, and analysed. It was found that the sample data contained a presence of hippuric acid, eicosane and octadecanal, along with several other biomarkers for the condition.

Commenting on the discovery, Professor Perdita Barran, from the University of Manchester, said the results could lead to the development of an early diagnostic test for the disease.

“Now we have proved the molecular basis for the unique odour associated with Parkinson’s we want to develop this into a test,” she said.

“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, added: “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.”