A recent study has illuminated significant genetic connections between irritable bowel syndrome (IBS) and mental health disorders, including anxiety, depression, bipolar disease, and schizophrenia.
Researchers from the University of Oslo and the University of Bergen in Norway, as well as the University of California in the US, have unveiled insights that delve into the intricate interplay between our brain and gut. Moreover, these findings hold potential for enhancing IBS treatments.
Employing a novel statistical method developed by a team member, the researchers conducted an analysis encompassing data from 53,400 individuals with IBS and 433,201 controls. Their aim was to identify genomic risk loci, specific sites within DNA sequences where gene variants could suggest an elevated risk for particular health conditions.
Both IBS and mental health conditions, as polygenic traits, are influenced by an array of genes. In this study, several of these genes were found to be shared. The research pinpointed 70 distinct loci where gene variants indicate susceptibility to IBS. Intriguingly, 7 of these genes are also associated with generalized anxiety disorder, 35 with major depression, 27 with bipolar disorder, and 15 with schizophrenia.
“In our published paper, we highlight the extensive polygenic overlap between IBS and psychiatric disorders, and to a lesser extent, gastrointestinal diseases,” wrote the researchers.
Globally, nearly 1 in 10 individuals live with IBS, a condition characterized by cramps, pain, and diarrhea. Although its origins remain uncertain, there is a general consensus that IBS is linked to how the brain responds to gut nerves.
This study reinforces that connection on a genetic level, providing new avenues for researchers and healthcare professionals to explore the intricate links between the gut and brain. The research also sheds light on pathways contributing to IBS that do not involve the nervous system, potentially offering alternative avenues for treatment.
While the researchers did not delve deeper into the mechanisms underlying the genetic overlap, they suggest that intestinal inflammation might lead to bacterial leakage into the bloodstream, eventually reaching the brain. This phenomenon could result in behavioral and cognitive changes, potentially explaining the high prevalence of IBS alongside psychiatric disorders.
Scientific exploration into the connection between our brains and digestive systems continues, uncovering insights such as the protective effect of education on gut health and the role of specific bacteria in the development of conditions like Alzheimer’s.
“This study broadens our comprehension of the genetic underpinnings of IBS and its relationships with gastrointestinal and psychiatric disorders,” commented Markos Tesfaye, a postdoctoral fellow at the Institute of Clinical Medicine at the University of Oslo.
The findings have been published in Genome Medicine.
