A unique circular RNA expression pattern in the peripheral blood of myalgic encephalomyelitis/chronic fatigue syndrome patients.
Cheng, Yuning, Xu, Si-Mei, Takenaka, Konii et al. · Gene · 2023 · DOI
Quick Summary
Researchers looked at a special type of genetic material called circular RNA (circRNA) in the blood of ME/CFS patients and healthy people, measuring it before and after exercise. They found that ME/CFS patients have a different pattern of circular RNAs compared to healthy controls, and unlike healthy people, ME/CFS patients didn't show the normal increase in these molecules after exercise. The study identified 14 specific circular RNAs that were present in ME/CFS patients but completely absent in healthy controls, suggesting these could potentially be used as markers to help diagnose the disease.
Why It Matters
ME/CFS currently lacks objective diagnostic markers, leading to widespread underdiagnosis and diagnostic delays. This study identifies the first circRNA biomarker signature specific to ME/CFS, potentially enabling blood-based diagnosis and providing new insights into the disease's molecular mechanisms. If validated, these 14 circRNAs could transform clinical diagnosis and help researchers better understand what drives ME/CFS pathology.
Observed Findings
ME/CFS patients showed higher total circRNA detection compared to healthy controls in peripheral blood
Healthy controls demonstrated an increase in circRNA abundance following exercise testing, while ME/CFS patients showed no similar increase
14 circRNAs were highly expressed in all ME/CFS patients but completely absent in all healthy controls throughout the longitudinal study
Differentially expressed circRNAs showed lack of correlation with their corresponding linear RNA genes in expression patterns
Five of the 14 ME/CFS-specific circRNAs had predicted miRNA targets enriched in protein and gene regulatory pathways
Inferred Conclusions
Unique circRNA expression patterns may serve as objective molecular biomarkers for ME/CFS diagnosis
The aberrant circRNA response to exercise in ME/CFS patients reflects physiological differences distinct from healthy individuals
CircRNAs appear to function as independent biomarkers in ME/CFS, not merely as byproducts of their parent genes
The 14 ME/CFS-specific circRNAs represent a novel molecular signature with potential mechanistic involvement in disease pathways
Remaining Questions
Do these 14 circRNAs have diagnostic utility in larger, independent cohorts, and what are their sensitivity and specificity for ME/CFS diagnosis?
What This Study Does Not Prove
This study does not prove that circRNAs cause ME/CFS symptoms or that any of these biomarkers are responsible for the disease; it only demonstrates association. The findings require validation in larger, independent patient populations before clinical implementation. Additionally, the study does not explain why circRNA patterns differ or what role they play in disease pathogenesis—only that they are present.