Suchergebnisse

Optimal health care delivery requires an understanding of genetic diversity and its associated risks. Population genomics is a rapidly emerging field that will yield such knowledge. As we are entering the genomic era, the need to develop policies and strategies integrating genetic determinants of health into medical services, health promotion and disease prevention is becoming increasingly important, perhaps inevitable. To this end, the Quebec Network of Applied Genetic Medicine (RMGA) supports a multidisciplinary and integrative research strategy which combines Quebec's expertise in population and community genetics. The present article briefly describes two projects developed with a view to foster such strategy. The ECOGENE-21 project is designed to develop and evaluate resources and strategies for integrating and transferring new knowledge of the human genome to individuals, families and communities. ECOGENE-21 will be capitalizing on another project called CART@GENE, which is generating a combined genetic and demographic map containing information on allelic variation in the subpopulations of Quebec. These two projects are complementary and will be integrated with the ultimate goal of transferring knowledge gained from basic research, to promote health improvement and disease prevention.

In the Saguenay-Lac St. Jean (SLSJ) region of Quebec, the high prevalence of some hereditary diseases has led concerned community members to create the Corporation for Research and Action on Hereditary Diseases (CORAMH) to take an active part in seeking and providing answers to this important health issue. CORAMH performs an important and unique role in the reciprocal transfer of information between community and researchers, as well as in the promotion and development of specialized services and research. It also provides a meeting ground for dialogue and dissemination of information. In particular, since 1983, CORAMH has been offering a Hereditary Disease Information and Prevention Program, mainly to SLSJ high-school clientele to convey basic genetic notions and provide information on specific hereditary diseases and on genetic determinants of health. By rallying various actors around a common table, CORAMH has come to be viewed as a community representative and can thus conduct effective mediations with decisional authorities for the development of proper health services. CORAMH also participates in reflection and research projects, such as ECOGENE-21, that aim to develop exportable infrastructures in preventive and community genetics and vanguard scientific, medical, ethical and social approaches capable of improving the population's quality of life. CORAMH offers an intervention model that can be applied to specific hereditary disorders or complex diseases and serve other communities which will be requiring interventions on the genetic determinants of health in the upcoming decades.

Familial hypercholesterolemia (FH) is one of the most common inherited metabolic diseases, and is associated with an increased cardiovascular risk. The diagnosis of FH is based on clinical criteria, but molecular DNA testing is available, and has proven to be helpful in risk assessment. In addition, new technologies could be applied to FH, such as high-density DNA probe arrays and gene therapy. The use of genetic information, however, raises specific ethical concerns which indicate that DNA testing for FH should not be performed blindly. Before consenting to molecular testing, an individual must really understand FH, what risks it involves for himself as well as his family and community, and what the treatment entails. Since the cardiovascular risk of FH patients is affected by other susceptibility genes and environmental factors, an individual should be able to assess the impact of this additional risk on his health outcome. In this regard, the ethical issues raised by a simple trait such as FH may help define a community genetic approach for a complex trait such as coronary artery disease.

Hypertension is a complex disease in which environment and heredity interact. It is a polygenic trait that can be studied by investigating its intermediate phenotypes. We have selected the population from the Saguenay-Lac St. Jean region because it is a relative genetic isolate. We have found that the prevalence of hypertension at every age level was greater than in a control Canadian population. A sib pair analysis was used to measure familial correlation and heritability of more than 200 phenotypes among which were renal functions, anthropometric measures and cardiac morphology and reactivity. Very strong familial correlations were estimated for several cardiovascular phenotypes. During a pharmacological infusion of norepinephrine, we observed that systolic blood pressure was increased as expected but that the heritable component of this phenotype increased from null at baseline to close to 70%. Preliminary total genome scans completed on the DNA of the participants have selected several regions linked to these phenotypes. This type of study opens the door to pharmacogenetic studies in which sib pairs are analyzed for their concordant or discordant response to a medication.