New Gene Helps Fight Diabetes in Canadas Abo


New Gene Helps Fight Diabetes in Canadas Aboriginal PopulationLONDON, ON (March 9, 1999) -- It was announced today, that scientists at The John P. Robarts Research Institute have discovered a new genetic mutation in the Oji-Cree people residing on the Sandy Lake reserve in Northern Ontario. This was part of a collaboration involving Robarts, the community of Sandy Lake, The University of Western Ontario and Mount Sinai Hospital.This is the strongest genetic effect on diabetes that I have seen in fifteen years of research. I am unaware of any other diabetic population in the world so strongly affected by a single gene variant, says Dr. Robert Hegele*, Director of the Blackburn Cardiovascular Genetics Laboratory at Robarts. He led a team of genetic researchers at Robarts who discovered the mutation.The results will be published in the March 9, 1999 issue of the prestigious Journal of Clinical Endocrinology and Metabolism. This study was funded by the Canadian Diabetes Association (CDA) and the Medical Research Council of Canada (MRC)**. Dr. Hegeles collaborators were Dr. Stewart Harris, of the Centre for Studies in Family Medicine at The University of Western Ontario, and Dr. Bernard Zinman, a clinical scientist at the Samuel Lunenfeld Research Institute, Mount Sinai Hospital and University of Toronto. The work was carried out in partnership with the community of Sandy Lake in Northern Ontario.The mutation was found using DNA sequence analysis. The researchers found that the diabetic adults had a high frequency of a mutation, called G319S, which affects the structure of a liver protein called hepatic nuclear factor-1 alpha, or HNF-1a.Dr. Hegeles team found that a person who inherited one copy of the G319S mutation from their parents was more than twice as likely to have diabetes as someone who did not inherit the mutation. An individual who inherited two copies of the G319S mutation was up to 15 times more likely to have diabetes. People with one copy of the mutation, on average, developed diabetes in their 30s. Those with two copies of the mutation, on average, developed diabetes in their 20s.The discovery of the HNF-1a G319S mutation is an important new clue that could help efforts to fight diabetes in Canadas native people, explains Dr. Hegele. The discovery of this gene could pave the way for preventative measures that could be taken by those individuals who are identified through the presence of the G319S mutation, to be at high risk of developing diabetes. It will likely also give clues to better treatments for those members of the Sandy Lake band that already have diabetes and thus help delay or prevent the onset of complications due to the disease.This discovery compliments the ongoing diabetes prevention program begun by Dr. Zinman, Dr. Harris and the Sandy Lake Community in 1995.This discovery will enhance our extensive and ongoing community-wide program involving nutrition education and exercise in accordance with CDA practice guidelines. In addition, the community program incorporates a school-based diabetes prevention curriculum whose objective is to delay or prevent the development of diabetes by teaching healthy lifestyles practices in children in grades three to five, says Dr. Zinman. There was no significant finding of this particular genetic mutation in any other major ethnic groups in Canada, indicating that this mutation is specific to the Oji-Cree of Northern Canada. It has always been known that there is more than one gene that causes diabetes, but this study shows that diabetes-causing genes may be specific to individual ethnic groups.This discovery is a major contribution to further our ongoing research, says Dr. Harris. Diabetes is emerging as a major epidemic among First Nations populations across North America and there is an urgent need to develop strategies to assist communities to deal with this major public health issue.The Oji-Cree of Northern Ontario have the worlds third highest prevalence of type 2 diabetes. The prevalence of diabetes in the Oji-Cree is 25%, which is more than five times higher than that in the general Canadian population.Diabetes is a serious disease that affects over 2 million Canadians, comments Dr. Thomas McDonald, past Chair of the CDA National Research Council and also a Robarts scientist. This disease leads to such complications as heart disease and stroke, blindness, kidney failure and gangrene. In addition to the heavy toll on individuals and families, these complications extract a high social and economic cost. The treatment of complications due to diabetes, test the limits of an already stressed health care delivery system, especially for those native people who live on isolated reserves.The Canadian Diabetes Association is the largest non-governmental supporter of diabetes research in Canada. CDA ensures that it funds only the best quality research projects, through an intensive internal and external peer review process. Last year alone, CDA dedicated $4.5 million to diabetes research. The John P. Robarts Research Institute is Canadas only privately operated medical research facility.*Dr. Hegele is also Professor, Department of Medicine at The University of Western Ontario and an Endocrinologist at London Health Sciences Centre.** Other funding for this project came from Health Canada, the Ontario Ministry of Health and The Employees of the Blackburn Group of Companies and The Blackburn Family.-30-For more information, please contact:Dr. Robert Hegele, Director, Blackburn Cardiovascular Laboratory, The John P. Robarts Research Institute Phone: (519) 663-3461OrJan Graves, Director of Communications and Development, The John P. Robarts Research InstitutePhone: (519) 663-5777 ext. 34334