To explore the causal relationship between testosterone and endometriosis, andto identify and quantify the role of gut microbiota as a potential mediator through Mendelian randomization analysis.
Utilizing the summary data from the IEU GWAS database for testosterone (n=199 569) and endometriosis (8 288 cases and 68 969 controls) as the exposure and outcome variables, and the aggregated gut microbiota data from the MiBioGen Consortium (n=18 340) as the mediator, a bidirectional, two-step Mendelian randomization analysis was conducted. Causal relationships were assessed using inverse varianceweighted, MR-Egger, weighted median, weighted model, and simple modelto assess causality, while sensitivity analysis was conducted to ensure the robustness of the findings.
Impact of testosterone on endometriosis:Inverse variance weighted estimates suggested that testosterone had negative causal effects on endometriosis (OR=0.804, 95%CI:0.670-0.964, P=0.018).Impact of endometriosis on testosterone:Reverse Mendelian randomization showed that endometriosis did not present a causal effect on testosterone (OR=0.991, 95%CI:0.958-1.026, P=0.616).The class Melainabacteria, one of the gut microbiotas, accounted for a 17.21% reduction in the risk of endometriosis associated with testosterone (mediation proportion: 17.21%, 95%CI:0.090-0.264, P=0.035).
Testosterone is one of the protective factors of endometriosis.Low testosterone levels increase the risk of endometriosis.Gut microbiota may be a mediator of the causal effect of testosterone on endometriosis.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |