However, the emergence of the AHR–microbiota axis prompted us to expand insights into other GI diseases, and AHR activity-related diseases including Alzheimer’s disease (Salminen, 2023), arthritis (Rosser et al., 2020), cardiovascular disease (Paeslack et al., 2022), psoriasis (Qiao et al., 2022), and so on. The gene discussed is AHR; the disease is arthritic joint disease.