Gene variant linked to IBS
An international team of researchers, lead from Karolinska Institutet in Sweden, have found that a variant of a gene called TNFSF15 is significantly associated with increased risk of Irritable Bowel Syndrome (IBS), the most common gastrointestinal disorder worldwide. The findings are presented in the journal GUT.
"Although a genetic component is suspected in IBS, unambiguous susceptibility genes have so far not been identified", says corresponding author, Associate Professor Mauro D'Amato. "We tested the hypothesis that genes contributing to epithelial barrier integrity, control of mucosal immune responses and interactions with bacteria in the gut are associated with IBS."
In the current study, data from 1992 individuals from two independent case-control cohorts from Sweden and USA were used. The researchers studied 30 genes known to predispose to the intestinal disease Crohn's disease, and identified a gene variant in TNFSF15 that appears to increase also the risk of IBS. Further tests were performed on specific subgroups of patients characterized by constipation (IBS-C), diarrhea (IBS-D) or alternating constipation and diarrhea (IBS-A), and the TNFSF15 gene was found to have a more pronounced effect in the IBS-C group.
"TNFSF15 contributes to the modulation of inflammatory responses and, provided our results are replicated in other populations, this finding further supports a role of immune activation in IBS", says Mauro D'Amato.
Today, IBS affects more than 10 percent of the general population worldwide. Its diagnosis is based on a combination of symptoms including abdominal pain, bloating, constipation, and diarrhea. In addition to researchers at Karolinska Institutet, researchers at the Mayo Clinic, US, University of Pittsburgh School of Medicine, US, Örebro University Hospital, Umeå University, Skåne University Hospital and Gothenburg University participated in the study.
Association of TNFSF15 polymorphism with irritable bowel syndrome.
Gut 2011 Dec;60(12):1671-1677