Compared to healthy individuals, irritable bowel syndrome (IBS) patients expressed higher levels of VIP and tryptase, increased numbers of MCs, a higher percentage of MCs that expressed VPAC1, and increased bacterial passage, which was significantly diminished after blocking with anti-VPACs and ketotifen, demonstrating that mechanisms of increased translocation included MCs and VIP [94]. This evidence concerns the gene VIPR1 and irritable bowel syndrome.