Grant: Environments, Genes and Chronic Disease - LOI

Inflammatory bowel diseases (IBD) are heterogeneous inflammatory diseases that affect the gastrointestinal tract. IBD constitute a very significant threat to the health of Canadians, as this country has the highest prevalence of IBD in the world. Both genetics and environmental factors contribute to IBD pathogenesis. While the genetic basis of the disease is now better defined, it is very different among racial groups, complicating the understanding of disease pathogenesis. In contrast to Canada, Japan has a moderate incidence of IBD, but this has been rapidly increasing over the last three decades, suggesting that an environmental factor underlies this rise. Diet is an important modifier of the microbiome hence a potential modulator of IBD. Diet has been markedly different between Japanese and Western populations in the past, but this is changing. The distinct genetic and dietary contexts in Canada and Japan, provide a unique comparative opportunity to investigate how dietary components interact with genetic risk loci, and with the intestinal microbiome to promote IBD in two distinct populations. We propose a multi-center research program that aims to identify environmental nutritional factors that may modulate the penetrance and expressivity of host genetic risk, by altering content and metabolic activity of the microbiome. Such studies will not only identify individuals at risk, but may provide better diagnostic tools, and may further inform possible nutritional modification programs to diminish incidence and improve outcomes.