title: Deviations in human gut microbiota: a novel diagnostic test for determining dysbiosis in patients with IBS or IBD.
abstract: BACKGROUND
  Dysbiosis is associated with many diseases, including irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD), obesity and diabetes. Potential clinical impact of imbalance in the intestinal microbiota suggests need for new standardised diagnostic methods to facilitate microbiome profiling.
  
  
  OBJECTIVE
  To develop and validate a novel diagnostic test using faecal samples to profile the intestinal microbiota and identify and characterise dysbiosis.
  
  
  METHODS
  Fifty-four DNA probes targeting ≥300 bacteria on different taxonomic levels were selected based on ability to distinguish between healthy controls and IBS patients in faecal samples. Overall, 165 healthy controls (normobiotic reference collection) were used to develop a dysbiosis model with a bacterial profile and Dysbiosis Index score output. The model algorithmically assesses faecal bacterial abundance and profile, and potential clinically relevant deviation in the microbiome from normobiosis. This model was tested in different samples from healthy volunteers and IBS and IBD patients (n = 330) to determine the ability to detect dysbiosis.
  
  
  RESULTS
  Validation confirms dysbiosis was detected in 73% of IBS patients, 70% of treatment-naïve IBD patients and 80% of IBD patients in remission, vs. 16% of healthy individuals. Comparison of deep sequencing and the GA-map Dysbiosis Test, (Genetic Analysis AS, Oslo, Norway) illustrated good agreement in bacterial capture; the latter showing higher resolution by targeting pre-determined highly relevant bacteria.
  
  
  CONCLUSIONS
  The GA-map Dysbiosis Test identifies and characterises dysbiosis in IBS and IBD patients, and provides insight into a patient's intestinal microbiota. Evaluating microbiota as a diagnostic strategy may allow monitoring of prescribed treatment regimens and improvement in new therapeutic approaches.
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: C
authors.initials: C
authors.lastname: Casén
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: H C
authors.initials: HC
authors.lastname: Vebø
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Sekelja
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: F T
authors.initials: FT
authors.lastname: Hegge
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: M K
authors.initials: MK
authors.lastname: Karlsson
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Ciemniejewska
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Dzankovic
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: C
authors.initials: C
authors.lastname: Frøyland
authors.affiliation: Genetic Analysis AS, Oslo, Norway.
authors.forename: R
authors.initials: R
authors.lastname: Nestestog
authors.affiliation: Karolinska Institute, Stockholm, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Engstrand
authors.affiliation: Department of Gastroenterology, Northzealand Hospital, University of Copenhagen, Copenhagen, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Munkholm
authors.affiliation: Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark.
authors.forename: O H
authors.initials: OH
authors.lastname: Nielsen
authors.affiliation: Clinic for Gastroenterology and Hepatology, University of Zürich, Zürich, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Rogler
authors.affiliation: Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Simrén
authors.affiliation: Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Öhman
authors.affiliation: EpiGen Institute, Campus Ahus, Institute of Clinical Medicine, University of Oslo, Lørenskog, Norway.|Section of Gastroenterology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: M H
authors.initials: MH
authors.lastname: Vatn
authors.affiliation: Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
authors.forename: K
authors.initials: K
authors.lastname: Rudi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001419:Bacteria / Q000302:isolation & purification; D003955:Diagnostic Tests, Routine / Q000379:methods; D064806:Dysbiosis / Q000175:diagnosis*; D005243:Feces / Q000382:microbiology; D005260:Female; D000069196:Gastrointestinal Microbiome; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000382:microbiology*; D043183:Irritable Bowel Syndrome / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D009664:Norway; D055815:Young Adult