Five intestine-making genes identified

GENEVA, Switzerland, October 19, 1999 - The conclusions of a Department of Zoology and Animal Biology study, conducted by professor Denis Duboule and Dr József Zákány for the Faculty of Science, will be published in the October 21 1999 edition of the prestigious journal Nature. The researchers identified five genes that play a role in the making of the digestive tube.

The digestive tube is made up of various elements, such as the colon and the small intestine, each with a specific function. The different segments of the intestine acquire their specificities during the development of the embryon; in most cases they are separated from each other by muscular constrictions called sphincters. Sphincters control the transit of the alimentary bolus and ensure that the digestive system functions smoothly.

Professor Duboule and Dr Zákány identified the five genes that regulate the making of sphincters, situated one after the other on a chromosome. To establish the importance of the five genes in the intestine-making process, the researchers removed them using genetic microsurgery from a mouse, which subsequently gave birth to animals without sphincters, suffering from intestinal problems. Studies of this kind allow a deeper comprehension of the origins of certain diseases linked to badly-formes intestines. The researchers, based in Geneva, also underlined that the five genes resembled genes already identified in flies. We can thus deduce that the genetic process identified by the researchers has been present for a considerable amount of time, from an evolutionary point of view. It was probably part of the intestine-making process of the common ancestor of mammals and insects!

'Hox Genes and the making of sphincters', Professor Denis Deboule and Dr József Zákány, Nature, October 1 1999.