Notably, mucin breakdown as driven by certain human gut commensals, including B. bifidum may consequently trigger the secretion of additional colonic mucin, thus recovering or even increasing the thickness of the total load of mucus layer present on the mucosa, thereby reinforcing the epithelial barrier function, which represents an important feature especially in those subjects affected by irritable bowel syndrome [150]. This evidence concerns the gene MUC5AC and irritable bowel syndrome.