title: Molecular characterization of the intestinal microbiota in patients with and without abdominal bloating.
abstract: Recent studies have demonstrated differences in the intestinal microbiota between patients with irritable bowel syndrome (IBS) and healthy controls (HC), suggesting a role for the intestinal microbiota in the pathogenesis of IBS. Alterations in the microbiota have also been implicated in the pathogenesis of abdominal bloating, a commonly reported symptom in IBS. We investigated the relationship between the intestinal microbiota, abdominal bloating, and altered bowel patterns in a cohort of patients with IBS and HC. The 16S rRNA gene from fresh fecal samples was amplified and pyrosequenced by using Roche-454 Titanium chemistry. A Core Measurable Microbiome (CMM) was generated for Operational Taxonomic Unit (OTU) detected in >75% of all samples and compositional features of CMM were compared between groups by Linear Discriminant Analysis (LDA). IBS differentiated from HC by LDA using continuous variation in the species/OTUs or the CMM genera. When subcategorized based on bloating symptoms and bowel characteristics, the same subjects were also well differentiated from one another and from HC. ANOVA analysis showed quantitative species/OTU differences between the subgroups including IBS with and without bloating, and subtypes based on bowel characteristics. The clear LDA differentiation and the significant microbial taxa differences between the groups imply a significant association of the microbiota with bloating symptoms and bowel characteristics in IBS. These changes in the microbiota may serve as a biomarker for IBS and its clinical subtypes and suggest a role for the intestinal microbiota in the pathogenesis of the main symptoms of the disorder.
authors.affiliation: Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina;
authors.forename: Tamar
authors.initials: T
authors.lastname: Ringel-Kulka
authors.affiliation: Core for Applied Genomics and Ecology and Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska;
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Benson
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and.
authors.forename: Ian M
authors.initials: IM
authors.lastname: Carroll
authors.affiliation: Core for Applied Genomics and Ecology and Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska;
authors.forename: Jaehyoung
authors.initials: J
authors.lastname: Kim
authors.affiliation: Core for Applied Genomics and Ecology and Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska;
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Legge
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and Center for Functional Gastrointestinal and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina ringel@med.unc.edu.
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Ringel
mesh_terms: D034841:Abdominal Cavity; D000328:Adult; D015331:Cohort Studies; D004269:DNA, Bacterial / Q000235:genetics; D004108:Dilatation, Pathologic; D005243:Feces / Q000737:chemistry / Q000382:microbiology; D005260:Female; D000069196:Gastrointestinal Microbiome; D006801:Humans; D007422:Intestines / Q000382:microbiology* / Q000503:physiopathology*; D043183:Irritable Bowel Syndrome / Q000382:microbiology / Q000503:physiopathology; D008297:Male; D064307:Microbiota; D008875:Middle Aged; D012336:RNA, Ribosomal, 16S / Q000096:biosynthesis / Q000235:genetics; D055815:Young Adult
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA gene; abdominal bloating; intestinal microbiota; irritable bowel syndrome; pyrosequencing