Project 170018

The use of genetic tests to identify people who face an increased disease risk is growing in Canada. The social marketing of gene tests contains two misleading messages: i) the prices for tests are low and will continue to decline; and ii) gene test results will allow doctors to make highly accurate individual diagnoses and treatment decisions. These messages are misleading because the price of tests alone ignores social costs such as additional health care utilization, and the clinical utility of most gene tests is far from definitive. While the message implies genetic certainty, in fact many gene tests will produce ambiguous results. When combined with phenotypic (i.e. blood) tests, many people will fall in abiguous categories. In the case of hereditary hemochromatosis, twelve different combinations result. For two of these combinations, there is sufficient medical evidence to provide people with clear advice to follow-up with their doctor. A third combination results in no detectable abnormalities, and clear advice that no further follow-up is warranted. The remaining nine combinations, however, are ambiguous in terms of specific disease risk and appropriate follow-ups. This study is set up to examine changes in the number and type of visits to physicians as well as increased health care costs in those who received ambiguous screening results in a study of 20,000 Canadians.

investigation of mast cell activation for cancer therapy