Scientists have shown for the first time that people may inherit some of the intestinal bacteria that cause Crohn’s disease and ulcerative colitis, collectively know as inflammatory bowel disease (IBD).
The study by an international team of researchers also confirmed that antibiotics could worsen the imbalance in the gut microbes.
About 1.6 million Americans suffer from Crohn’s disease or ulcerative colitis, according to the Crohn’s and Colitis Foundation of America.
“The intestinal bacteria, or ‘gut microbiome’, you develop at a very young age, can have a big impact on your health for the rest of your life,” said the study’s lead author Dan Knights, a University of Minnesota assistant professor in the Department of Computer Science and Engineering and the Biotechnology Institute.
“We have found groups of genes that may play a role in shaping the development of imbalanced gut microbes,” Knights said.
Knights and his colleagues at the University of Minnesota worked with collaborators at Harvard, MIT, University of Toronto and University Medical Center Groningen in one of the largest international studies of its kind.
The researchers examined three independent cohorts of a total of 474 adults with IBD who live in Boston (US); Toronto, Ontario (Canada); and Groningen (Netherlands).
Doctors and nurses in those locations collected samples of DNA from each human subject and the DNA of their intestinal bacteria over about a two-year period. The researchers looked at thousands of microbial species and human genes.
The results, which were replicated across two or more cohorts, showed that the human subjects’ DNA was linked to the bacteria in their intestines. Patients with IBD had lower biodiversity of bacteria and more opportunistic bacteria.
The study also confirmed that use of antibiotics is associated with a greater imbalance in the bacterial community in the intestines.
Previous studies have shown links between human gut bacteria and increased risk of a wide variety of diseases including diabetes, autism, heart disease and even some forms of cancer.
The study was published in journal Genome Medicine.