In IBS-A/M patients, between-group comparison showed no significant differences in 5-HT4R expressions in the colonic tissue between any two of the three groups (37.07 ± 8.19 versus 32.62 ± 14.81 versus 42.07 ± 6.04, all P > 0.05). The gene discussed is HTR4; the disease is irritable bowel syndrome.