Recent Findings in PPMI

by Krishna Knabe
The Michael J. Fox Foundation

A group of authors led by PPMI’s principal investigator, Dr. Kenneth Marek, published baseline data from the study in the Annals of Clinical and Translational Neurology. The paper includes detailed biomarker signatures on the initial volunteer groups, which include patients with Parkinson’s disease, healthy controls and those who had scans without evidence of dopaminergic deficit (SWEDD). (SWEDD patients present with motor symptoms consistent with Parkinson’s, but brain imaging scans do not find disease pathology.) The paper also shares details on the study’s rigorous design and methodology. This baseline data is critical to understanding how these patients progress and how best to measure that progression.

In 2012, Professor Miratul Muqit discovered a “molecular switch” affected by PINK1 and PRKN, two genes involved in early-onset forms of Parkinson’s. Dr. Muqit had seen the switch in laboratory conditions, but no one had identified its role in humans until this year. Researchers found two patients — including one in the PPMI study — who have mutations in this molecular switch (called Serine 65). The findings, published in Open Biology, will help facilitate the development of therapies targeting this critical process.

One of the advantages of PPMI is that the depth and breadth of the data it contains can lead to unexpected findings. A group of researchers using several datasets, including PPMI, found that removal of the appendix was associated with lower risk of developing Parkinson’s disease as well as a delayed age of onset. The findings were published in Science Translational Medicine. MJFF’s Vice President of Medical Communications Dr. Rachel Dolhun says of the study: “It’s a piece to the puzzle. It suggests protein misfolding might happen in peripheral organs to be an initiating factor in [Parkinson’s] disease, and that the appendix might be an organ that could contribute.”

We look forward to keeping you up to date on more important findings made using PPMI data in 2019.