Activation of Transposable Elements in Immune Cells of Fibromyalgia Patients.
Ovejero, Tamara, Sadones, Océane, Sánchez-Fito, Teresa et al. · International journal of molecular sciences · 2020 · DOI
Quick Summary
Researchers discovered that fibromyalgia patients have unusual activity of genetic sequences called transposable elements (pieces of DNA that can move and copy themselves) in their immune cells. This overactivity was linked to higher levels of interferon proteins, which trigger inflammation and flu-like symptoms. This finding may help explain why fibromyalgia patients often feel sick even when they don't have an actual infection.
Why It Matters
Since ME/CFS and fibromyalgia frequently co-occur and both involve unexplained inflammatory symptoms, understanding shared genetic dysregulation mechanisms could lead to better diagnostic markers and targeted therapies. This work identifies a potentially modifiable immunological pathway that affects a large subset of FM patients and may inform future ME/CFS biomarker research.
Observed Findings
HERVs of types H, K, and W are overexpressed in immune cells of fibromyalgia patients
Patients with increased HERV expression showed elevated interferon-β and interferon-γ levels
TNF-α levels remained unchanged despite elevated interferon levels
Findings were observed in FM patients both with and without comorbid ME/CFS
Sample of 14 patients with increased HERV expression demonstrated this pattern
Inferred Conclusions
HERV dysregulation is associated with abnormal interferon signaling in fibromyalgia and may contribute to flu-like symptoms without active infection
The interferon-dominant immune response (elevated IFN with unchanged TNF-α) suggests a specific immunological phenotype in FM
TE dysregulation may represent a shared molecular mechanism between fibromyalgia and ME/CFS
Remaining Questions
Do specific genomic loci show differential HERV expression in FM versus ME/CFS versus both conditions combined?
Is HERV overexpression a cause or consequence of the interferon-dominant immune state in fibromyalgia?
Can HERV expression levels serve as a biomarker for predicting symptom severity or treatment response in fibromyalgia?
What This Study Does Not Prove
This study does not prove that HERV activation causes fibromyalgia or ME/CFS symptoms—it shows only an association in a small patient group. The study cannot establish whether HERV overexpression is a primary driver of disease or a consequence of immune dysregulation. It also does not identify which specific genomic loci are affected or establish therapeutic relevance.