Walkerton Tragedy: 10 years of research leads to breakthrough
McGill, McMaster researchers identify genetic risk markers
for Post-Infectious Irritable Bowel Syndrome
Studies of the victims of the Walkerton, Ont. tainted drinking
water tragedy have led researchers to discover DNA variations in
genes that increase the risk of developing post-infectious
irritable bowel syndrome (PI-IBS). The sheer scale of infection and
the recording of the health of Walkerton’s citizens gave a team of
researchers a unique opportunity to study the origin of this
disorder.
“Although the exact cause of PI-IBS remains unknown, we now know
for the first time that, in addition to the environmental trigger,
genetic factors are also playing a critical role in the development
of this disease,” explains McGill PhD Alexandra-Chloé Villani, who
led the team under the direction of principal investigators John K.
Marshall (McMaster) and Denis Franchimont (formerly of McGill).
Stephen Collins (McMaster) also collaborated.
Almost 10 years ago, the municipal water supply of Walkerton was
contaminated with E. coli and Campylobacter jejuni, leading to a
public health disaster. Seven people died and 2,300 suffered
symptoms, including bloody diarrhea. Of these 2,300, 36 per cent
developed PI-IBS, giving the town the highest incidence of PI-IBS
ever reported.
PI-IBS is a functional bowel disorder that has an acute onset after
an episode of gastroenteritis. “These patients suffer from chronic
abdominal pain, discomfort, bloating and disturbed defecation in
the absence of any detectable structural or biochemical
abnormalities,” said Marshall, a gastroenterologist. “After the
exclusion of known organic disorders, like Crohn’s disease and
ulcerative colitis, such patients are diagnosed with PI-IBS.”
“The biological implications of the identified genetic risk factors
emphasize the important roles of the gut microbial flora,
intestinal barrier function and inflammatory pathways in
contributing to the onset of PI-IBS,” Villani explained. Though
these results will not lead to any new short-term treatments for
PI-IBS, Marshall is confident that in the longer term the research
will lead to better patient care, including potentially novel
therapeutic targets for research, as well as improved medical
decision-making (“risk stratification”) concerning victims of
future outbreaks.
The details of the study will be published in the March edition
journal Gastroenterology (available online at gastrojournal.org).
The study was supported by the Crohn’s & Colitis Foundation of
Canada (CCFC) and the Ontario Ministry of Health and Long-Term
Care. McGill’s Villani is affiliated with the Ď㽶ĘÓƵ and
Genome Quebec Innovation Centre. Marshall and Collins are both at
the Michael G. DeGroote School of Medicine, McMaster University.
Marshall is Associate Professor of Medicine, a Full Member of the
Farncombe Family Digestive Health Research Institute and Head of
Clinical Research for the Division of Gastroenterology. He is also
an active consultant gastroenterologist at Hamilton Health
Sciences. Collins is a Professor of Medicine and Associate Dean for
Research, Faculty of Health Sciences and holds the GlaxoSmithKline
Chair in Gastroenterology. Franchimont, now with the Erasme
Hospital in Brussels, Belgium, was a Canada Research Chair formerly
affiliated with the Gastroenterology Department at McGill
University Health Centre (MUHC).
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About the :
The Ď㽶ĘÓƵ and GĂ©nome QuĂ©bec Innovation Centre is
financed by Genome Canada and the Ministère du Développement
économique, de l’innovation et de l’exportation of Quebec, and
provides complete DNA analysis services, from a few samples to
several tens of thousands per week. Ambitious DNA sequencing
projects carried out over the past five years are testimony to
Génome Québec’s ability to provide data of exceptional quality in
the pursuit of various genomics studies. Large-scale genomics
projects at the Innovation Centre are highly integrated together on
three platforms: sequencing, genotyping and functional genomics
supported by an infrastructure and unique expertise in
bioinformatics. High-quality protein separation and analysis
services are also provided by the proteomics platform.
About McMaster University and the :
The Farncombe Family Digestive Health Research Institute is an
integrated group of clinical and basic scientists dedicated to
understanding the causes of chronic digestive diseases. The
Institute is focused on developing new strategies for the
diagnosis, treatment and prevention of intestinal diseases such as
Crohn’s disease and ulcerative colitis, which will have global
benefits. Formerly known as the Intestinal Diseases Research
Program (IDRP), the newly established Institute was established
with a $15-million gift from the Farncombe family. The generous
contribution, which includes four endowed chairs and infrastructure
capital, will ensure the long-term success of the Institute and
enhance its role as an innovative training environment. For more
than 20 years, McMaster’s Intestinal Diseases Research Program has
garnered an international reputation as one of the top 10
gastrointestinal research groups in the world. The growth in
research funding, faculty awards and now the expansion into a
Research Institute is a testament to the critical role McMaster
researchers are playing in the study of gastrointestinal
diseases.