Insulin being released into bloodstream to bind glucose

Investigating genome-environment interactions in diabetes

September 22, 2015

Type 1 diabetes is a disease in which the pancreas does not produce insulin, resulting in glucose accumulation in the blood instead of being used for energy.

The Challenge

Type 1 Diabetes (T1D) is a complex disease often arising in childhood in which the immune system destroys the insulin producing cells of the pancreas. Insulin is a crucial hormone in sugar and fat metabolism. Despite insulin therapy, T1D greatly increases the probability of heart attack, stroke, blindness and limb amputation, as well as shortened life expectancy.

  • Canada has the third largest incidence of T1D in the world, affecting some 200,000 Canadians, including 45,000 – 90,000 Ontarians
  • Ontario spends $5 billion a year on diabetes and associated conditions

The Research Solution

T1D is caused by multiple genetic risk factors and currently unknown environmental factors. Now an innovative research project is investigating the interactions of genetic risks and environmental factors underlying T1D.

Dr. Jayne Danska, Senior Scientist at Toronto’s Hospital for Sick Children and Professor in the Faculty of Medicine at the University of Toronto, and Dr. Andrew Macpherson, Canada Research Chair in mucosal immunology at McMaster University, are involved in a project that aims to understand how genetics can be used to control T1D in humans and rodent models. They will also study how exposure to common intestinal bacteria affects the development of the immune system and how such exposures affect the probability that people at genetic risk of T1D will develop the disease.

This project is expected to discover new genetic markers and identify environmental exposures that increase T1D risk, with the long-term aim of reducing disease risks through therapeutic intervention.

Successes to date

Several genes involved in diabetes have been discovered in tests carried out with mice. These tests have identified potential ways to help improve the immune systems in people with diabetes

The tests with mice has led to the building of a unique germ-free mouse facility in Toronto – one of only two in North America – that enables genomic analysis of animals with specific bacterial exposures under controlled conditions. This facility with its state-of-the-art technology will speed up research into diabetes and help discoveries be made quicker

This research is making great leaps towards reaching the ultimate goal of understanding how T1D is affected by environmental conditions, and armed with this understanding, researchers will be able to predict the body’s immune systems reaction to various treatments and environments, and even manipulate environmental factors to block or stop the development of the condition.

Associated Integrated GE3LS Research Project: Attitudes of Adults and Adolescents to Predictive Genetic Testing for Diabetes