Molecular analysis of the gut microbiota of identical twins with Crohn's disease

• Increasing evidence suggests that a combination of host genetics and the composition of the gut microbiota are important for development of Crohn's disease (CD). Our aim was to study identical twins with CD to determine microbial factors independent of host genetics. Fecal samples were studied from 10 monozygotic twin pairs with CD (discordant n=6 and concordant n=4) and 8 healthy twin pairs. DNA was extracted, 16S rRNA genes were PCR amplified and T-RFLP fingerprints generated using general bacterial and Bacteroides group-specific primers. The microbial communities were also profiled based on their percentage G+C contents. Bacteroides 16S rRNA genes were cloned and sequenced from a subset of the samples. The bacterial diversity in each sample and similarity indices between samples were estimated based on the T-RFLP data using a combination of statistical approaches. Healthy individuals had a significantly higher bacterial diversity compared to individuals with CD. The fecal microbial communities were more similar between healthy twins than between twins with CD, especially when these were discordant for the disease. The microbial community profiles of individuals with ileal CD were significantly different from healthy individuals and those with colonic CD. Also, CD individuals had a lower relative abundance of B. uniformis and higher relative abundances of B. ovatus and B. vulgatus. Our results suggest that genetics and/or environmental exposure during childhood, in part, determine the gut microbial composition. However, CD is associated with dramatic changes in the gut microbiota and this was particularly evident for individuals with ileal CD.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Gastroenterologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Gastroenterology and Hepatology (hsv//eng)

Nyckelord

Adolescent

Adult

Aged

Bacteroides/classification/genetics/*isolation & purification

Base Composition

Biodiversity

Cohort Studies

Crohn Disease/*microbiology

DNA; Bacterial/genetics

DNA; Ribosomal/genetics

Diseases in Twins/*microbiology

Feces/microbiology

Female

Gastrointestinal Tract/*microbiology

Humans

Male

Middle Aged

Multivariate Analysis

Polymorphism; Restriction Fragment Length

RNA; Ribosomal; 16S/genetics

Sweden

MEDICINE

MEDICIN

Internal medicine

Invärtesmedicin

Gastroenterology

Gastroenterologi

Invärtesmedicin

Internal Medicine

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)