MONTREAL (May 5, 2005) -- Quebec researchers today announced that they have created a genetic database that offers hope for improved diagnosis and treatment of high blood pressure (hypertension), a condition that affects about five million adult Canadians. A team led by Dr. Pavel Hamet of Montreal, in partnership with Dr. Daniel Gaudet in Saguenay, studied 120 French-Canadian families in the Saguenay-Lac St. Jean region in Quebec for genetic markers for hypertension on their chromosomes. Researchers found 46 significant chromosomal areas associated with hypertension and its cardiovascular and metabolic consequences. This study was primarily funded by the U.S. National Heart, Lung, and Blood Institute (NHLBI), through the Specialized Centers of Research (SCOR) Program. Dr. Hamet's work is further supported by the Institute of Circulatory and Respiratory Health (ICRH) of the Canadian Institutes of Health Research (CIHR), the Heart and Stroke Foundation of Canada (HSFC), the Canada Foundation for Innovation, and Valorisation Recherche Québec. The study is being published in the prestigious American Journal of Human Genetics in May 2005. "We have taken an important step towards the day when we will be able to diagnose the genetic cause of an individual's hypertension by simple blood test," says Dr. Pavel Hamet, lead investigator, Director of Research at the Centre hospitalier de l'Université de Montréal (CHUM). "By genetically identifying the underlying cause, treatment could become more tailored to the individual, the family and even entire ethnic groups." "The potential benefits of Dr. Hamet's findings to patients and to the health care system are considerable," says Dr. Bruce McManus, Scientific Director of CIHR's Institute of Circulatory and Respiratory Health. "In the future this work may help us determine the likelihood of an individual developing hypertension and a target gene for treatment." "For those individuals who can't manage their hypertension through a healthy lifestyle, treatment is necessary," says Gloria Sacks Silver, Director of Research for the Heart and Stroke Foundation of Quebec and spokesperson for the Heart and Stroke Foundation of Canada. "Dr. Hamet's work is an important step in our knowledge of hypertension - a significant risk factor for heart disease and stroke. Better detection and treatment of this condition could save thousands of lives each year." Currently, each anti-hypertension medication works in only about 50% of patients. As a result doctors may have to prescribe several medications, and time is lost as doctors work to find the right combinations for each patient. Anti-hypertensive medications can also cost the healthcare system over $1,500 a year per person and some people are not getting the full benefits of their medication, which could be achieved if their treatment targeted the appropriate genes responsible. Dr. Hamet's research focuses on 120 French-Canadian families - 900 individuals - living in the Saguenay-Lac-St. Jean region. Many of these families are direct descendants of the original settlers who came to New France in the 17th century. Their genealogical records from 1680 to the present have been computerized and are available to the researchers through the systematic effort of Prof. Gérard Bouchard and his team at the Université du Québec à Chicoutimi (UQAC). Together, they have developed a computerized demographic and genealogical register (the BALSAC Database) covering the majority of the Quebec population from the 17th through the 20th century. The research team spent two days running tests on each individual studied within the families, examining all forms of cardiovascular function and scanning their genomes. Family members were screened for 250 clinical characteristics and their genome scanned with 400 genetic markers. "We are now in a position to discover which genes are susceptible or resistant to stress, nutrition, or to the socio-economic factors associated with hypertension," says Dr. Hamet. "People in the Saguenay do not have more hypertension than the rest of Canada - it's just that the genes that cause hypertension are easier to find, because the family histories are known. By working in this region, we could take full advantage of the BALSAC Database." The success of these research findings are the result of a team effort between CHUM and the Chicoutimi Hospital (both Université de Montréal) and researchers from five universities: École Polytéchnique de Montréal, UQAC, McGill, University of Ottawa, and MIT. Significant contributions also came through a long standing collaboration with researchers of the Medical College of Wisconsin through the SCOR Program directed by Dr. Allen W. Cowley Jr. "Hypertension is a common, complex disease in an area where past successes were mainly restricted to simple, monogenic diseases," comments Prof. Cowley. "Choice of this specific population, its comparison with other populations in the United States, detailed phenotyping and multidisciplinary approach led to the success of this study." The leadership of Ettore Merlo in bio-informatics and Daniel Gaudet, from the Université de Montréal Community Genomic Medicine Centre in Chicoutimi were also critical to successfully deciphering this disease "We have laid the groundwork for the novel concept of a quantitative founder effect, in which a trait determined within a set of families is measurably and quantitatively transmitted throughout generations contributing to a specific component of the disease," concludes Pavel Hamet. Dr. Hamet's work is supported through the 'Gene-Environment Interactions in Circulatory and Respiratory Health' program led by ICRH and HSFC. In 2002, his team was awarded an Interdisciplinary Health Research Team (IHRT) grant for a total of $2.6 million over five years. The aim of this research is to better understand genetic and environmental interactions - something that is already happening after three years, and should lead soon to the development of targeted and preventive interventions in cardiovascular disorders. - 30 - May 14, 2005 is World Hypertension Day. The CIHR Institute of Circulatory and Respiratory Health and the Heart and Stroke Foundation of Canada are two of the partners in this initiative to increase awareness of prevention, management and treatment of hypertension in Canada. The Canadian Institutes of Health Research is the Government of Canada's agency for health research. Its objective is to excel, according to internationally accepted standards of scientific excellence, in the creation of new knowledge and its translation into improved health for Canadians, more effective health services and products and a strengthened Canadian health care system. Composed of 13 Institutes, CIHR provides leadership and support to more than 9,000 researchers and research teams in every province of Canada. The Heart and Stroke Foundation is a leading funder of heart and stroke research in Canada. The Foundation's mission is to improve the health of Canadians by preventing and reducing disability and death from heart disease and stroke through research, health promotion and advocacy. The Centre hospitalier de l'Université de Montréal (CHUM) provides specialized and subspecialized services to a regional and supraregional clientele. Within its more immediate coverage area, it also offers general and specialized hospital care and services. All of these services contribute to teaching, research, the assessment of technologies and healthcare methodologies, which are provided within integrated networks. The CHUM also contributes to promoting health in continuity with front-line services. Hôtel-Dieu, Hôpital Notre-Dame and Hôpital Saint-Luc form the CHUM, which counts 10,000 employees, 900 physicians, 330 researchers, 5000 students and trainees, and 800 volunteers, who provide services to more than 500,000 patients each year. The Medical College of Wisconsin, a private academic institution in Milwaukee, dedicated to leadership and excellence in education, patient care, research and community service, has rapidly risen to national prominence in many areas of health care and biomedical sciences. Founded in 1893, it is dedicated to leadership and excellence in education, patient care, research and service. Last year, its 1,100 faculty physicians and scientists received nearly $123 million in federal and private grants to conduct more than 1,500 medical research studies. The Medical College is at the forefront of discovering the genetic influences of complex diseases such as hypertension, renal failure and cancer. The National Heart, Lung, and Blood Institute (NHLBI) is part of the National Institutes of Health (NIH), the Federal Government's primary agency for biomedical and behavioral research. NIH is a component of the U.S. Department of Health and Human Services. Additional information about hypertension and NHLBI-supported research and educational programs can be found online at www.nhlbi.nih.gov. Nancy Radford Heather Rourke Fondation des maladies du coeur du Québec Heart and Stroke Foundation of Canada (514) 871-8038, ext. 232 (613) 569-4361, ext 318 Lise Provost, B.Sc., M.Ed. Senior external communications advisor Centre hospitalier de l'Université de Montréal (CHUM) Tel.: (514) 890-8000, ext. 15380 Pager: (514) 860-7110 Janet Weichel, Media Specialist Canadian Institutes of Health Research (613) 447-4794
