Genetic variants in serotonin genes may be responsible for Irritable Bowel Syndrome (IBS), according to new research by the Mayo Clinic. While serotonin is often associated with the brain, 95 percent of it is found in the gastrointestinal tract, forming a 'second brain' in the body. The findings from the Mayo Clinic also indicate that IBS may be caused by multiple genes, as well as overlapping molecular mechanisms that cause diarrhea and constipation, two of the major symptoms of IBS.
IBS is a common, chronic disorder of the digestive tract, causing chronic abdominal pain and bowel function disturbance. It can include bouts of diarrhea, chronic constipation, or vacillation between the two. IBS can limit a person's professional and social life.
The research at the Mayo Clinic included using high throughput technology. The technology studied nearly 400 tagged single-nucleotide polymorphisms (SNPs) in over 20 serotonin-related genes.
"Rather than sending out a few patrol cars to look for culprits by rounding up 'the usual suspects,' we launched a genetic dragnet that took an objective, unbiased look at a broader range of possibilities," said Yuri Saito, M.D., Mayo Clinic gastroenterologist and presenter of the study.
What they found was that many serotonin-related SNPs were implicated in IBS, all relating to serotonin synthesis, metabolism and receptors. They also found that there may be more than one gene causing IBS, overlapping and causing the signs and symptoms of IBS.
The research findings from the Mayo Clinic offer future researchers targets for developing new drugs, therapies and treatments for IBS.
