Moreover, increased SP, VIP, CGRP, CRH, and 5-HT were observed in IBS patients and experimental IBS animals (Keszthelyi et al., 2013; Yu et al., 2016; Ceuleers et al., 2018; Fu R. et al., 2019; Guilarte et al., 2020). The gene discussed is VIP; the disease is irritable bowel syndrome.