Taking it a step further, the team identified healthy people, overweight people and Crohn’s disease-affected people with the genetic variant and analyzed their gut microbiomes under the leadership of co-senior author Jonathan Braun, MD, PhD, chair and professor of pathology and laboratory medicine in the David Geffen School of Medicine at UCLA. That is how they discovered that the genetic variant is not just linked to Crohn’s and other conditions, but also to a reduction in hundreds of species of gut bacteria.
“Many of these species are believed to play roles in protecting the intestine against Crohn’s disease, and also in preserving a lean body physiology,” said Dr. Braun. “So, this may be an example where the gene increases risk for disease via its effect on types of bacteria we need to preserve our health.”
The findings have sparked additional questions and potential research avenues, but therapies are still quite a ways off, said Dr. Duerr, also a professor in the Pitt Graduate School of Public Health Department of Human Genetics. However, the recent establishment of the University of Pittsburgh Center for Medicine and the Microbiome will help accelerate this research and bring potential therapies—which may involve the center’s clinical fecal transplantation program—to patients.
“This study illustrates the remarkable interaction between our proper genome and our symbiome—the organisms and environment inside and outside of us that influence our well-being—in the setting of inflammatory bowel disease,” said Mark T. Gladwin, MD, chair of medicine and Dr. Jack D. Myers Professor of Internal Medicine at Pitt. “Insights from this study are likely to guide the development of microbiome modulating therapies that hold the promise to alleviate patient suffering.”
Additional institutions with researchers who participated in this study are Cleveland Clinic; Yale University; Karolinska Institutet and Örebro University, both in Sweden; Biocruces Health Research Institute in Spain; University Hospital Munich-Grosshadern, University of Ulm, Krankenhaus Waldfriede and Ludwig-Maximilians-University, all in Germany; QIMR Berghofer Medical Research Institute, Royal Brisbane and Women’s Hospital and University of Queensland, all in Australia; Inselspital Bern and University Hospital Basel, both in Switzerland; Emory University; University of Chicago; Harvard University; Université de Montréal, Hôpital Maisonneuve-Rosemont, University of Toronto and Montreal Heart Institute, all in Canada; Icahn School of Medicine at Mount Sinai; University of California Riverside; The Children’s Hospital of Philadelphia; Massachusetts Institute of Technology; and Johns Hopkins University.
Additional support for this research was provided by numerous grants to the individual researchers, as listed in the Gastroenterology research publication.