Some of the down-regulated genes in diarrhoea-susceptible sheep, including MYH11, CACNB2, ATP1A2, CAV3, PRKG1, FOXP2 and FBXO32, normally maintain a physiological and homeostatic environment in the gut, so their down-regulation would increase the severity of diarrhoea through, for example, disruption of gut absorptive function. The gene discussed is CACNB2; the disease is Diarrhea.