AUTHOR=Zhang Ruiqiao , Zhao Weijie , Zhao Ruijie , Zhao Yunhai , Zhang Yanlong , Liang Xuezhi TITLE=Causal relationship in gut microbiota and upper urinary urolithiasis using Mendelian randomization JOURNAL=Frontiers in Microbiology VOLUME=Volume 14 - 2023 YEAR=2023 URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1170793 DOI=10.3389/fmicb.2023.1170793 ISSN=1664-302X ABSTRACT=Background:Several reports in recent years have found an association between gut microbiota and urinary stones. However, the causal relationship between them remains to be clarified. Methods: Genetic variation is used as a tool in Mendelian randomization for inference whether exposure factors have a causal effect on disease outcomes. We selected summary statistics from a large genome wide association study of the gut microbioma published by the MiBioGen consortium as an exposure factor and urolithiasis data from FinnGen GWAS as a disease outcome. Then a two-sample Mendelian randomization analysis was performed by applying Inverse variance weighted, MR-Egger ,maximum likelihood,and weighted median. In addition, sensitivity analysis was done to avoid bias of the results. Results: IVW results confirmed that Barnesiella(OR = 0.695,95%CI:0.551–0.877,P = 2.20 × 10−3), Clostridium sensu_stricto_1(OR = 0.777,95%CI:0.612–0.986,P = 0.0380), Flavonifractor(OR = 0.711,95%CI:0.536–0.944,P = 0.0181), Hungatella(OR = 0.829,95%CI:0.690–0.995,P = 0.0444) and Oscillospira(OR = 0.758,95%CI:0.577–0.996,P = 0.0464)had a protective effect on renal stones while Eubacterium xylanophilum(OR =1.26,95%CI:1.010–1.566,P = 0.0423) had the opposite effect in total 119 genera. Sensitivity analysis did not find outlier SNPs. Conclusion:In conclusion, a causal relationship was found between several genera and urinary stones. However, we still need further randomized controlled trials to validate.