In murine models, AHR-deficient mice (AHR−/−) were more sensitive to dextran sodium sulfate (DSS)-induced colitis (Monteleone et al., 2011; Basu et al., 2012; Chinen et al., 2015; Schiering et al., 2017), showed higher levels of pro-inflammatory cytokines than wild-type (WT) (namely AHR+/+) controls, and more severe colitis-related symptoms and clinical outcomes (Takamura et al., 2010; Arsenescu et al., 2011; Furumatsu et al., 2011; Metidji et al., 2018; Wang et al., 2018). This evidence concerns the gene AHR and colitis.