Dr. Kenneth Croitoru

An association between a unique set of human genes and the makeup of the microbiome has been discovered. This finding offers new insights into the link between the community of bacteria living in human bodies, known as the microbiome, and numerous diseases it impacts such as inflammatory bowel disease (IBD), diabetes and rheumatoid arthritis. The new study, published in Nature Genetics, reveals that the microbiome is not only impacted by environmental factors, but also by our genes.

Findings reveal that among the 1,561 healthy individuals involved in the study, nearly 25 per cent of whom were related, one-third of the bacteria within participants’ microbiome had a heritability factor. In addition, four specific genes were found to have links to specific bacteria types within participants’ gut microbiome.  This suggests that our genetics influence what types of bacteria may inhabit our gut.

The study was led by Dr. Kenneth Croitoru (a Clinician-Scientist in Sinai Health System’s Zane Cohen Centre for Digestive Research, Scientist with the Lunenfeld-Tanenbaum Research Institute and a Professor of Medicine in the Division of Gastroenterology at the University of Toronto) and Dr. Andrew Paterson (a Senior Scientist at the SickKids Research Institute and a Professor at the University of Toronto’s Dalla Lana School of Public Health).

“As an inflammatory bowel disease specialist, I have seen a consistent pattern of heritability of this devastating disease. This study sets the stage to define how our genetic makeup and its relation to our gut microbiome may explain disease. The challenge ahead of us is to explore the impact of that genetic link, and how we can use this new information to prevent and treat disease,” said Dr. Kenneth Croitoru.

These new findings are part of a larger study known as the Crohn’s and Colitis Canada Genetics, Environmental, Microbial (GEM) Project, a major international study being led by Dr. Kenneth Croitoru at Sinai Health System and the University of Toronto to determine the cause of IBD (Crohn’s disease and ulcerative colitis), debilitating conditions that affect one in 150 Canadians. The GEM Project is collecting data from healthy family members of patients with IBD to track those who develop the disease. The data from GEM was used in this microbiome study.

“The genetic analysis of the microbiome from healthy subjects gives us important insight into the possible interplay between our genetic makeup and microbial factors that influence health and disease,” said Dr. Andrew Paterson. “Understanding these possible interactions may have implications for many diseases associated with altered microbiome.”

Funding for this study was provided by The Canadian Institutes of Health Research (CIHR), Crohn’s and Colitis Canada and The Leona M. and Harry B. Helmsley Charitable Trust.

Mina Mawani, President and CEO of Crohn’s and Colitis Canada welcomed the findings, adding, “for people living with Crohn’s disease and ulcerative colitis this research provides exciting insights which will help advance our search for the causes and cures of inflammatory bowel disease.”

To read the full study, click here.

About Sinai Health System

Sinai Health System is comprised of Mount Sinai Hospital, Bridgepoint Active Healthcare, Lunenfeld-Tanenbaum Research Institute and Circle of Care. As an integrated health system, it delivers exceptional care from healthy beginnings to healthy aging, especially for people with specialized and complex health needs, in hospital, community and home. Sinai Health System discovers and translates scientific breakthroughs, develops practical health solutions, educates future clinical and scientific leaders and leads efforts to eliminate health inequities. Its Lunenfeld-Tanenbaum Research Institute ranks in the top ten biomedical research institutes in the world. Sinai Health System is a full affiliate of the University of Toronto. www.sinaihealthsystem.ca


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Sinai Health System
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