- Dual oxidase2 is expressed all along the digestive tract. El Hassani, R.A., Benfares, N., Caillou, B., Talbot, M., Sabourin, J.C., Belotte, V., Morand, S., Gnidehou, S., Agnandji, D., Ohayon, R., Kaniewski, J., Noël-Hudson, M.S., Bidart, J.M., Schlumberger, M., Virion, A., Dupuy, C. Am. J. Physiol. Gastrointest. Liver Physiol. (2005)