The cause and effect of gut microbiota in development of inflammatory disorders of the breast

BACKGROUND: Inflammatory disorders of the breast (IDB) damages the interests of women and children and hinders the progress of global health seriously. Several studies had offered clues between gut microbiota (GM) and inflammatory disorders of the breast (IDB). The gut–mammary gland axis also implied a possible contribution of the GM to IDB. However, the causality between them is still elusive. METHODS: The data of two-sample Mendelian randomization (MR) study related to the composition of GM (n = 18,340) and IDB (n = 177,446) were accessed from openly available genome-wide association studies (GWAS) database. As the major analytical method, inverse variance weighted (IVW) was introduced and several sensitive analytical methods were conducted to verify results. RESULTS: Inverse variance weighted revealed Eubacterium rectale group (OR = 1.87, 95% CI: 1.02–3.43, p = 4.20E−02), Olsenella (OR = 1.29, 95% CI: 1.02–1.64, p = 3.30E−02), Ruminiclostridium-6 (OR = 1.53, 95% CI: 1.08–2.14, p = 1.60E−02) had an anti-protective effect on IDB. Peptococcus (OR = 0.75, 95% CI: 0.60–0.94, p = 1.30E−02) had a protective effect on IDB. The results were credible through a series of test. CONCLUSIONS: We revealed causality between IDB and GM taxa, exactly including Ruminiclostridium-6, Eubacterium rectale group, Olsenella and Peptococcus. These genera may become novel biomarkers and supply new viewpoint for probiotic treatment. However, these findings warrant further test owing to the insufficient evidences. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40001-023-01281-6.