In the population level, SLC9A8 exhibits widely pleiotropic influence on chronic inflammatory diseases including ankylosing spondylitis, Crohn’s disease, psoriasis, primary sclerosing cholangitis, and ulcerative colitis (Stuart et al., 2010; Ellinghaus et al., 2016); in addition, SLC9A8 is also associated with psoriasis (Stuart et al., 2010), gut microbiota (beta diversity) (Wang et al., 2016) and multiple sclerosis (International Multiple Sclerosis Genetics Consortium, 2013). This evidence concerns the gene SLC9A8 and Crohn disease.