The US Genetics and Public Policy Center at John Hopkins University, has called for increased regulation of direct to consumer genetic tests by the Food and Drug Administration (FDA). The recommendation follows a policy analysis, the results of which were published in the journal Science last week.
The group focused their study on genetic tests for CYP450 enzymes, which are instrumental in breaking down selective serotonin reuptake inhibitors (SSRIs), medicines used to treat depression. The companies marketing the tests claim that CYP450 genetic testing will give valuable information concerning the type of SSRI a person should take and the level of dose. However, the new report argues that this claim is unproven. While the FDA has certified that the test detects CYP450, it did not require the manufacturers to prove its usefulness to determine appropriate medication.
The report recommends that the FDA adopts closer regulation of genetic tests, especially those that are sold direct to consumer (DTC); creates a publicly accessible registry providing information about all available genetic tests; and increases its powers to prevent false or misleading claims regarding the benefits of genetic testing. Sara Katsanis, an analyst at the Genetics and Public Policy Centre, warned: 'testing has a place in this society - but oversight needs to catch up so that the public doesn't get misinformed'.
In 2007 the Evaluation and Genomic Applications in Practice and Prevention (EGAPP) committee reported that the clinical evidence did not support the use of the CYP450 genetic tests to guide SSRI use. Despite this companies have continued to market the tests DTC. Howard Coleman, CEO of one such company - Genelex - has complained that the EGAPP standard is too high. He explained, 'we don't have clear clinical outcome studies, but I don't think there's any question that these genes do affect the levels of drugs in these patients'.
Despite pressure, the FDA has been reluctant to clamp down on misleading claims in DTC genetic testing. While the FDA sets high standards for specialised gene tests, most of the DTC tests marketed are lab-developed tests. Gail Javitt, a legal specialist at the Genetics and Public Policy Center, confirmed that the FDA did not oversee the vast majority of tests, commenting, 'their position is that they could regulate the process - but they're not going to'.
There are fears that patients taking the CYP450 test could stop taking their medication, or change the dose, on the basis of the results they receive. However, such results should be interpreted by doctors, and put into the wider context of the patient's lifestyle.