Several genetic studies have highly correlated mutations in NOD2 domain with the development of Crohn’s disease (CD)1–4, though the mechanisms involved are still unclear, and perhaps linked to the NOD2 involvement in multiple processes, such as the preservation of intestinal barrier integrity and immune homeostasis, autophagy and balance of the gut microbiota composition5–7. The gene discussed is NOD2; the disease is Crohn disease.