“What should I do now, doctor?”
By AMY STURMS, MS, CGC, Clinical Assistant Professor Division of Human Genetics The Ohio State University Medical Center
It is difficult to watch television these days without seeing advertisements for pharmaceuticals. Recently, companies began marketing another type of healthcare product directly to consumers: genetic testing.
In the healthcare setting, genetic testing—the analysis of DNA to detect genetic alterations—is a valuable tool for disease diagnosis, estimating disease risk and predicting the response to certain therapies.
Direct-to-consumer (DTC) marketing of genetic testing involves two separate but related issues. The first is DTC marketing of genetic tests such as those for the BRCA1 and BRCA2 cancer susceptibility genes associated with the hereditary breast and ovarian cancer syndrome. Testing is ordered by a healthcare provider and results are provided back to the healthcare provider for provision to the patient. Previous DTC advertisements for breast and ovarian cancer genetic testing have increased demand for these tests, particularly among individuals with a relatively low risk of having a genetic mutation, many of whom are not appropriate candidates for testing.
The second issue is DTC marketing of a new wave of genetic tests that consumers can use at home. This type of testing is ordered by the consumer over the Internet, or by phone or mail. Results are returned directly to the consumer, and involvement of a healthcare provider is not required. As of May 2009, the Genetics and Public Policy Center identified at least 39 companies that offered such DTC testing for purposes ranging from determining ancestry to predicting athletic performance, hair loss or susceptibility to diseases such as cancer or mental illness.
The direct marketing and availability of these products raises multiple concerns that intersect at the levels of the consumer, the medical community, legislators and for-profit companies. Unlike pharmaceutical advertisements that include long lists of potential risks and side effects, advertisements for genetic testing tend to overstate the benefits and fail to adequately address the risks and limitations.
Currently, most DTC genetic testing companies offer genome-wide scans for panels of single nucleotide polymorphisms, or SNPs. Most of these SNPs are weak predictors of risk, accounting for only a fraction of the overall heritability of a trait or disease (the relative risk conferred by most SNPs is less than 2).
Experts in genetics and other areas of medicine have raised concerns regarding the clinical validity and utility of such testing. For example, does the test provide clinically significant information? Will the results affect medical decision-making? Does the test provide better information than simpler tests or the “gold standard” of family history?
As research improves our understanding of complex gene-gene and gene-environment interactions, risk level information will change and require updating. This may produce contradictory risk information over time that is likely to confuse consumers. However, proponents of DTC efforts contend that it may allow for greater consumer awareness and access to genetic tests, and allow consumers to take a more proactive role in their healthcare.
In 2008, the American College of Medical Genetics issued guidelines on DTC genetic testing and proposed the following minimum requirements:
- A knowledgeable professional should be involved in ordering and interpreting a genetic test;
- The consumer should be fully informed regarding what the test can and cannot say about his or her health;
- The scientific evidence on which a test is based should be clearly stated;
- The clinical testing laboratory must be accredited by the Clinical Laboratory Improvement Amendments (CLIA), the state or other applicable accrediting agencies;
- Privacy concerns must be addressed.
Currently, federal oversight of DTC genetic testing is limited, and no uniform or comprehensive system exists for assessing the validity of tests before they are made available to the public. According to a survey by the Genetics and Public Policy Center, 25 states and the District of Columbia permit DTC testing of different types without restriction, 13 states prohibit DTC testing, and 12 states permit only specified categories of tests and tend to exclude genetic tests.
What does all this mean for healthcare professionals? Physicians may find more of their patients requesting certain genetic tests and arriving at their office with genetic test results in hand—perhaps a 25-page report with complex findings for multiple diseases. How does the busy healthcare provider manage these requests to order and interpret genetic tests?
Multiple resources are available for assistance, including healthcare professionals with specialized training in genetics and genetic counseling who can serve as “genomic consultants.”
To find a genetic counselor in your area, visit the National Society of Genetic Counselors website, www.nsgc.org. To locate a certified geneticist, visit the American Board of Medical Genetics website, www.abmg.org. Information for the public is also available. The Federal Trade Commission offers a fact sheet on genetic testing for consumers at its website, www.ftc.gov, and the National Institutes of Health is developing a website for the public about DTC marketed genetic tests.
Genetic testing, combined with appropriate risk assessment, informed consent, education and support, can be a powerful tool that provides essential information regarding health risks to patients and their families, and to the physicians who care for them.
Whether DTC genetic tests will prove helpful to consumers remains to be seen, but many of those who use them are likely to turn to their physicians for help in understanding them.