Irritable bowel syndrome (IBS) is the most common gastrointestinal disorder, affecting 10-15% of people (women more than men) with symptoms including abdominal pain, bloating, constipation (IBS-C), diarrhoea (IBS-D) or both (IBS-M). Although not life-threatening, quality of life is reduced as much as in asthma, ischemic heart disease and similar common conditions.
While some contributing factors have been identified (stress, diet, gut microbiota and immune activation, bile acids malabsorption etc), IBS pathophysiology remains largely unknown, and there is no causative structural or biochemical abnormality that may be used for diagnostic or prognostic purposes. Symptom-based expert criteria (Rome Criteria) represent the current gold-standard for its classification in specialized centers and clinical research, though IBS diagnosis often remains one of exclusion in clinical practice, and therapy is mostly inefficient.
Because IBS etiopathogenesis is poorly understood, much hope is being put on genetic studies for the identification of causative pathways in order to inform and personalize treatment. Although genetic predisposition to IBS is recognized, genetic studies so far have been few and underpowered. IBS likely represents similar manifestations of several syndromes impacted by different genetic risk effects, hence its genetic study requires extremely large sample size.
With a pilot genome-wide association study (GWAS), we recently set precedent for the use of population-based samples in IBS research. We have now brought this approach to the next level, exploiting pan-European resources and existing genotype and phenotype data from a target population exceeding 800,000 Europeans. This is the bellygenes initiative, which represents an unmatched opportunity to tackle IBS genetics for the first time with adequate statistical power.
While some contributing factors have been identified (stress, diet, gut microbiota and immune activation, bile acids malabsorption etc), IBS pathophysiology remains largely unknown, and there is no causative structural or biochemical abnormality that may be used for diagnostic or prognostic purposes. Symptom-based expert criteria (Rome Criteria) represent the current gold-standard for its classification in specialized centers and clinical research, though IBS diagnosis often remains one of exclusion in clinical practice, and therapy is mostly inefficient.
Because IBS etiopathogenesis is poorly understood, much hope is being put on genetic studies for the identification of causative pathways in order to inform and personalize treatment. Although genetic predisposition to IBS is recognized, genetic studies so far have been few and underpowered. IBS likely represents similar manifestations of several syndromes impacted by different genetic risk effects, hence its genetic study requires extremely large sample size.
With a pilot genome-wide association study (GWAS), we recently set precedent for the use of population-based samples in IBS research. We have now brought this approach to the next level, exploiting pan-European resources and existing genotype and phenotype data from a target population exceeding 800,000 Europeans. This is the bellygenes initiative, which represents an unmatched opportunity to tackle IBS genetics for the first time with adequate statistical power.