Graves’ Disease Gut Microbiome Signature: Key Genera and Clinical Implications Original paper
Researched by:
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Giorgos Aristotelous
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Giorgos Aristotelous
Read MoreGiorgos — BSc, MSc. Giorgos is an exercise scientist whose training and professional practice sit at the intersection of human performance, clinical health, and emerging microbiome science. He holds a BSc in Sports Science & Physical Education from Aristotle University (2012) and an MSc in Exercise & Health from Democritus University (2016), where his graduate work explored physiological adaptations to training across the lifespan. Now in his 15th year of practice, Giorgos pairs evidence-based coaching (ACSM-CPT, NSCA, USA Weightlifting) with a research-driven interest in how physical activity, body composition, and musculoskeletal integrity shape—and are shaped by—host–microbiome dynamics.
Fact-checked by:
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Karen Pendergrass
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Karen Pendergrass
Read MoreKaren Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease—four years before the first published case study.
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Autoimmune Diseases
Autoimmune Diseases
Autoimmune disease is when the immune system mistakenly attacks the body's tissues, often linked to imbalances in the microbiome, which can disrupt immune regulation and contribute to disease development.
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Graves Disease
Graves Disease
OverviewGraves’ Disease (GD) affects approximately 0.5% of the population, predominantly women. First-line treatment options—antithyroid medications, radioactive iodine, and surgery— often result in significant side effects, incomplete remissions, and frequent relapses. Further, current first-line treatment options focus on symptoms management, and reflect an inadequate understanding of the etiology of the condition. However, recent research reveals a […]
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Giorgos Aristotelous
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Researched by:
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Giorgos Aristotelous
ID
Giorgos Aristotelous
Read More
Fact-checked by:
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Karen Pendergrass
ID
Karen Pendergrass
Read More
Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.
Giorgos Aristotelous
Location
China
Sample Site
Feces
Species
Homo sapiens
What was studied?
This prospective study evaluated the relationship between gut microbiota (GM) composition and Graves’ disease (GD), an autoimmune thyroid disorder, in newly diagnosed patients. Using 16S rRNA gene sequencing of fecal samples, the researchers profiled and compared the GM of 65 untreated GD patients and 33 healthy controls. They assessed microbiota changes before and after three months of antithyroid drug (ATD) therapy. The investigation aimed to identify specific microbial signatures associated with GD, measure their correlation with clinical parameters, and observe whether GM dysbiosis recovers following treatment. Additionally, a subgroup analysis examined differences in microbiota among GD patients with or without impaired liver function.
Who was studied?
A total of 98 individuals of Chinese Han ethnicity participated: 65 were newly diagnosed, untreated GD patients (18 men, 47 women; median age 30 years), and 33 were healthy volunteers (10 men, 23 women; median age 27 years) recruited from the First Affiliated Hospital of Nanchang University. The GD group met stringent diagnostic criteria (clinical symptoms, thyroid hormone and antibody levels, and ultrasound findings). Exclusion criteria included recent antibiotic/probiotic use, previous ATD therapy, gastrointestinal or other autoimmune diseases, liver disease, or pregnancy. Of the 65 GD patients, 37 completed three months of follow-up on methimazole. A subgroup of GD patients with impaired liver function (GDH) was also analyzed separately from those with normal liver function (GDN).
Most important findings
The study demonstrated that the gut microbiota composition of GD patients is significantly distinct from healthy controls. GD patients exhibited reduced alpha diversity (richness and diversity) of their GM, while beta diversity analyses confirmed a clear separation between groups. Specifically, the GD group showed increased abundance of Bacilli (class), Lactobacillales (order), Streptococcaceae (family), and the genera Streptococcus, Veillonella, and Erysipelatoclostridium. Conversely, there were reductions in families such as Peptostreptococcaceae, Christensenellaceae, Marinifilaceae, and Rikenellaceae, and in genera including Roseburia, Romboutsia, Lachnospira, and Eubacterium ventriosum—all associated with production of short-chain fatty acids (SCFAs) and anti-inflammatory effects.
Using a random forest model, 12 genera were identified that could distinguish GD patients from controls with high accuracy (AUC = 0.9021), making them strong candidates for microbiome-based GD biomarkers. Correlations were observed between specific bacterial genera and clinical indicators: for instance, Veillonella abundance was positively correlated with thyroid hormone levels (FT3, FT4) and thyrotrophin receptor antibodies (TRAb), while several SCFA-producing genera showed negative correlations.
After three months of ATD therapy, the GM of GD patients showed partial recovery: the abundance of previously increased taxa (e.g., Streptococcus, Streptococcaceae) decreased, while the abundance of SCFA-producers (e.g., Romboutsia, Lachnospira, Eubacterium ventriosum) increased. However, diversity remained lower compared to controls, and some dysbiosis persisted, indicating incomplete restoration of the microbiome. IL-17 levels, a marker of Th17-mediated immune response, decreased significantly post-treatment and were negatively correlated with Eubacterium hallii group abundance.
In GD patients with impaired liver function, reductions in Weissella and Leuconostocaceae were associated with liver injury markers, supporting a possible gut-liver axis in GD pathophysiology.
Key implications
The study establishes a robust microbiome signature for Graves’ disease, linking specific changes in gut microbial composition to disease presence and clinical parameters. The reduction in SCFA-producing, anti-inflammatory genera and the enrichment of pro-inflammatory bacteria suggest that GM dysbiosis may contribute to GD pathogenesis via immune modulation (e.g., Th17/Treg imbalance). Identification of 12 discriminatory genera provides a foundation for developing microbiome-based diagnostics or risk stratification tools for GD—potentially enabling earlier intervention before overt symptoms arise. The observed partial restoration of the GM following antithyroid therapy also suggests therapeutic modulation of the microbiome could complement GD management. The findings emphasize the importance of the gut-thyroid and gut-liver axes in autoimmune endocrine diseases, with implications for personalized medicine and the development of microbiome-targeted interventions.