A Causal Mediation Method with Methylated Region (MR) as the Mediator R package MRmediation version 1.0.1 A causal mediation approach under the counterfactual framework to test the significance of total, direct and indirect effects. In this approach, a group of methylated sites from a predefined region are utilized as the mediator, and the functional transformation is used to reduce the possible high dimension in the region-based methylated sites and account for their location information. Software Depends: R (>= 3.5.0), fda Imports: MASS, stats Qi Yan <qy2253@cumc.columbia.edu> Comprehensive R Archive Network (CRAN) Qi Yan GPL (>= 2) 2020-12-17 application/tgz https://CRAN.R-project.org/package=MRmediation doi:10.32614/CRAN.package.MRmediation