Fact Sheet on the So-Called "Breast Cancer Gene"

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Feminist Alliance on New Reproductive and Genetic Technologies

What is the "Breast Cancer Gene"?

The term "breast cancer gene" is misleading. There is no "breast cancer gene". But recently certain genes have been identified which are involved in increased susceptibility for breast cancer, and to a lesser extent ovarian cancer, in some women. This is relevant for a small percentage of breast cancers, where there are clear patterns of heredity - i.e. where a large number of close female relatives have had early onset breast and/or ovarian cancer. But susceptibility does not mean cause; it means an increased chance of getting cancer - over and above the average risk. Other biological features, or environmental experiences, or just chance, interact in complex ways to influence the likelihood of getting cancer.

In the last two years Myriad Genetics, an American-based biotechnology company, has isolated two genes linked to breast cancer in some women - BRCA1 and BRCA2. The company has filed for broad patents on both of these genes. A genetic screening test for BRCA1 was made commercially available in April 1996 by one private company. Meanwhile, Myriad Genetics expects to launch a major marketing program for BRCA1 in the second half of 1996. As part of the effort, Myriad is sending 30,000 physicians a detaile d package on genetic risks and a specific guide to interpreting cancer gene tests.

These events have led to a great deal of activity, both within Canada and internationally, as activists have sought to make public their opposition to both the patenting of human parts, products and processes and the commercial promotion of genetic scree ning tests for "susceptibility" to breast cancer.

What are the problems?

These genetic tests do not benefit women. They cannot prevent cancer. They cannot even reliably predict that any one of us will develop breast cancer. They are however, likely to lead to harmful and mutilating medical interventions of unproven efficacy, as women seek to prevent the onset of a cancer once identified as "high risk". But there are no proven preventive treatments for women without the disease. As well, the treatments that exist for women with the disease have failed to reduce mortality rates over the last fifty years. Meanwhile rates of breast cancer are increasing - and this is not because of our genes.

Women who undergo these tests risk losing their insurance or even their jobs once they are slapped with the stigma of a genetic "defect". The Boston-based Council for Responsible Genetics has documented over 200 cases in which healthy people were discri minated against because they carried genes linked to a risk of future disease. The danger of such discrimination in insurance or employment is very real and growing. The dangers are not just loss of insurance, women in the United States have also been p ressured to abort a fetus diagnosed as "defective" by companies who threaten the lost of health insurance.

Tests for BRCA1 and similar "cancer genes" benefit mainly the commercial companies that market them, who stand to make huge profits by exploiting women's justifiable fear of cancer. Their interest is in promoting these tests for population-wide screenin g. Such screening is used for asymptomatic persons - for those who show no sign of the disease. The test offers nothing to these women. There is absolutely no justification - save a commercial one - for the use of this test in screening. Even as a dia gnostic device for symptomatic women, or high risk women, its value is extremely questionable.

Furthermore, the excessive focus on genes as causing cancer, when environmental carcinogens are known to make major contributions, takes away attention from environmental clean-up measures that could, in fact, reduce the incidence of breast cancer. Fina lly, the focus on the individual's genes suggests that the problem lies with that woman, and implies that personal and private rather than social and systemic efforts are the most appropriate ways to seek for solutions and to provide support.