Author Contributions
J.H.K. and S.L. conceptualized the study design, and supervised the study, and wrote the manuscript. D.S. performed all statistical analyses, interpreted the results, and led the sequencing of the microbiome samples. Y.J.C. and M.Y.S. performed colonoscopic examinations and interpreted the results. W.M. and S.J.P. advised on data analysis and interpretation and edited the manuscript. All authors critically read the manuscript, and constructively commented on the intellectual content. All authors have read and agreed to the published version of the manuscript.