First-line anti-tumor necrosis factor alpha (anti-TNF) treatment with infliximab (IFX) (so-called “top-down” strategy) for children with moderate-to-severe Crohn's disease (CD), for instance, has recently been shown to convey advantages over conventional therapy in a 2020 randomized control trial (RCT) (1). This evidence concerns the gene TNF and Crohn disease.