For more than 11 million people with Parkinson's in 2021 (source), diagnosis came only after brain damage had already occurred. But what if diagnosing Parkinson’s was as simple as a routine blood test - detecting the disease years before symptoms appear? Today, researchers from the Hebrew University of Jerusalem have uncovered molecular patterns that could change how we understand Parkinson's disease and allow for earlier diagnosis and preventative treatment - potentially mitigating the disease's worst effects. 

 

Decoding Early Diagnosis

Researchers have developed a simple, affordable blood test that can detect Parkinson’s disease long before symptoms appear. They compare today’s methods for diagnosing neurodegenerative diseases to cancer detection 50 years ago—when most cases were caught too late for effective treatment. This new test could mark a turning point.

 

By analyzing small fragments of RNA in the blood, the test measures the ratio between two key molecular markers: a repetitive RNA sequence that increases in Parkinson’s patients, and a type of mitochondrial RNA that decreases as the disease progresses. The result is a fast, non-invasive, and highly accurate tool for early diagnosis—offering new hope for timely interventions that could slow or even stop disease progression.

 

The Challenge Ahead

Today, Parkinson’s and other neurodegenerative diseases are often diagnosed only after significant neuronal damage has occurred, making treatment far less effective. In response to this challenge, a team at the Hebrew University of Jerusalem has developed a breakthrough blood test that could revolutionize early detection of Parkinson’s disease (PD).

 

The study, recently published in Nature Aging, was led by PhD student Nimrod Madrer under the supervision of Prof. Hermona Soreq at The Hebrew University’s Edmond and Lily Safra Center for Brain Sciences (ELSC) and The Alexander Silberman Institute of Life Sciences, in collaboration with Dr. Iddo Paldor from Shaare Zedek Medical Center, and Dr. Eyal Soreq from the University of Surrey and Imperial College London.

 

Unlocking RNA Clues

The test introduces a new approach by examining transfer RNA fragments (tRFs)—small pieces of RNA that were previously overlooked in Parkinson’s research. These molecules can reflect changes in cellular processes associated with the disease. The researchers identified two key biomarkers: an increase in PD-associated tRFs containing a repeated sequence motif (called RGTTCRA-tRFs) and a decrease in mitochondrial tRFs (MT-tRFs).

 

By measuring the ratio between these two types, the test can accurately distinguish individuals in the early, pre-symptomatic stages of Parkinson’s from healthy controls—offering greater accuracy than current clinical tools.

 

“This discovery represents a major advancement in our understanding of Parkinson’s disease and offers a simple, minimally invasive blood test as a tool for early diagnosis,” said Prof. Hermona Soreq. “By focusing on tRFs, we’ve opened a new window into the molecular changes that occur in the earliest stages of the disease.”

 

“This discovery represents a major advancement in our understanding of Parkinson’s disease and offers a simple, minimally invasive blood test as a tool for early diagnosis,” - Prof. Hermona Soreq, The Hebrew University of Jerusalem

 

The test relies on a standard, dual qPCR assay, comparing the abundance of the repeated tRF sequence with a reference mitochondrial sequence. Because it uses widely available technology, the test is both cost-effective and suitable for routine use in a variety of clinical settings. In trials using samples from multiple international cohorts, including the Parkinson’s Progression Markers Initiative, the test demonstrated a diagnostic accuracy of 0.86, significantly outperforming traditional diagnostic scoring methods.

 

Mapping Treatment Progress

In addition to its diagnostic potential, the study found that RGTTCRA-tRF levels decrease after deep brain stimulation, a treatment commonly used for advanced Parkinson’s. This suggests that the biomarkers could also be used to monitor treatment response, deepening our understanding of how therapies affect the disease at the molecular level.

 

Lead author Nimrod Madrer emphasized the importance of detecting Parkinson’s early, before irreversible brain damage occurs. “This test has the potential to reduce the uncertainty faced by patients and clinicians by offering a reliable and rapid method to identify the disease in its earliest stages,” Madrer said.

 

“This test has the potential to reduce the uncertainty faced by patients and clinicians by offering a reliable and rapid method to identify the disease in its earliest stages,” - Nimrod Madrer, The Hebrew University of Jerusalem

 

The findings are now protected under U.S. Provisional Patent Applications, and larger-scale studies are underway to validate the test in broader clinical settings. This work marks a major milestone in Parkinson’s research and offers new hope for millions around the world.

 

The research paper, “Pre-symptomatic Parkinson’s disease blood test quantifying repetitive sequence motifs in transfer RNA fragments,” is now available in Nature Aging. Read it here: https://www.nature.com/articles/s43587-025-00851-z.

 

Researchers

• Nimrod Madrer, Shani Vaknine-Treidel, Tamara Zorbaz, Yonat Tzur, Estelle R. Bennett, David S. Greenberg, Hermona Soreq; The Edmond and Lily Safra Center for Brain Sciences; Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics and Science; The Hebrew University of Jerusalem
• Paz Drori; Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics and Science; The Hebrew University of Jerusalem
• Nitzan Suissa; The Neurosurgery Department, Shaare Zedek Medical Center, Jerusalem
• Eitan Lerner; Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics and Science; The Center for Nanoscience and Nanotechnology; The Hebrew University of Jerusalem
• Eyal Soreq; UK Dementia Research Institute Care Research and Technology Centre (UK DRI CR&T) at Imperial College London and the University of Surrey; Department of Brain Sciences, Faculty of Medicine, Imperial College London
• Iddo Paldor; Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics and Science; The Hebrew University of Jerusalem; The Neurosurgery Department, Shaare Zedek Medical Center, Jerusalem

 

For a century, the Hebrew University of Jerusalem has been a beacon for visionary minds who challenge norms and shape the future. Founded by luminaries like Albert Einstein, who entrusted his intellectual legacy to the University, it is dedicated to advancing knowledge, fostering leadership, and promoting diversity. Home to over 23,000 students from 90 countries, the Hebrew University drives much of Israel’s civilian scientific research, with over 11,000 patents and groundbreaking contributions recognized by nine Nobel Prizes, two Turing Awards, and a Fields Medal. Ranked 81st globally by the Shanghai Ranking (2024), it celebrates a century of excellence in research, education, and innovation. To learn more about the University’s academic programs, research, and achievements, visit the official website at http://new.huji.ac.il/en.