Also, a FUT2 effect on the microbiota composition was evidenced in a human cohort (n = 47, including 29 Crohn’s disease patients and 18 healthy controls) only when the inflammatory bowel disease variable was introduced in the analyses, which allowed a clear separation of secretor phenotypes by their microbiota composition [52] and also in an study carried out with pregnant women (n = 123, 15 non-secretors) [56], which reinforces the idea that the FUT2 effect may only became evident under certain circumstances. This evidence concerns the gene FUT2 and Crohn disease.