24 July 2008
Genome wide association (GWA) studies have identified a number of genetic variants associated with common conditions such as cardiovascular disease, diabetes and obesity. Such research has also resulted in an increasing number of genetic tests to determine the presence or absence of such variants, and to some degree predict genetic risk for these common diseases, although the clinical utility of many such tests is non-proven (see previous news). The biological mechanisms through which such genetic variants contribute to risk and how risk data can be utilised to improve health is still unclear. Such information is potentially valuable for developing therapies, as well as improving public health interventions such as population screening programmes (see previous news).
This month the US National Human Genome Research Institute (NHGRI) announced a funding programme which will grant $31million over four years for projects to investigate the relationship between genetic risk and health. The programme will focus on four existing epidemiological studies: National Health and Nutrition Examination Survey (NHANES), CALiCo Consortium, Multiethnic Cohort and Women's Health Initiative. These studies have been collecting medical information from participants for many years and consist of an ethnically diverse population; an important factor as many GWA studies are carried out in people of European descent and other ethnic groups may vary in the frequency of variants they possess. The researchers will investigate 100 genetic variants in 10, 000 participants each year for four years, and this information will be correlated with clinical characteristics, such as weight, cholesterol levels, blood sugar levels or bone density. They will also investigate the interaction between genetic and non-genetic (environmental) factors such as diet and medication and how this interaction influences health outcomes.
A co-ordinating centre funded by the US National Institute of Mental Health will be established to facilitate data access and analysis tools and data generated from each study will be deposited in the public database of Genotypes and Phenotypes (dbGaP). The NHGRI hope that this data will help translate genomic research into strategies to improve human health and “guide other genomic and epidemiologic studies by defining the potentially wide-ranging effects of genetic differences among people” (see press release).