Genetic clue to irritable bowel syndrome found

Researchers have reported a defined genetic defect that causes a subset of irritable bowel syndrome (IBS).

Researchers found that patients with a subset of IBS have a specific genetic defect, a mutation of the SCN5A gene. This defect causes patients to have a disruption in bowel function, by affecting the Nav1.5 channel, a sodium channel in the gastrointestinal smooth muscle and pacemaker cells.

Gianrico Farrugia, M.D., a study author, Mayo Clinic gastroenterologist and director of the Mayo Clinic Center for Individualized Medicine, said that this gives them hope that from only treating symptoms of the disease, they can work to find disease-modifying agents, which is where they really want to be to affect long-term treatment of IBS.

Researchers studied the sodium channel of 584 people with IBS and 1,380 control subjects. The analysis demonstrated that a defect in the SCN5A gene was found in 2.2 percent of IBS patients.

The results were confirmed in a genome-wide association study and replicated in 1,745 patients in four independent cohorts of patients with IBS and control subjects.

The research has been published in the journal Gastroenterology.