Home gene tests in the spotlight

Published Mar 7, 2011


Chicago - US health officials plan to ask advisers next week about the benefits and risks of direct-to-consumer genetic tests, including whether various kinds of tests should have to meet different regulatory standards, according to documents released on Friday.

The Food and Drug Administration for months has been weighing what to do about the increasingly popular test kits but grew concerned when Pathway Genomics in April announced a pact with Walgreen Co to distribute tests through its 6,000 neighbourhood pharmacies.

Pathway has since stopped selling its tests to consumers.

Unlike genetic tests ordered by doctors, genetic tests sold directly to consumers give people information about potential health risks online or in the mail. Regulators are worried people may not understand the limitations of the tests, or that they may take action on their own - such as not taking prescribed medication - without consulting a doctor.

Several companies - including Decode Genetics' DeCodeME based in Iceland, 23andME in which Google has invested, and privately held Navigenics - sell tests online that allow people to learn if they have inherited risk for disease.

In briefing documents released ahead of the advisory panel meeting on Tuesday and Wednesday, FDA said it will ask its outside experts to consider whether the tests can be placed into different categories, including genetic tests that look for inherited disease; tests that predict the risk of future disease, such as breast or ovarian cancer; and tests used to predict the treatment response to specific drugs.

The agency is also looking for input on the risks of incorrect or misunderstood results for testing done without counselling. And it wants the panel to determine what level of evidence is needed for direct-to-consumer genetic tests to make claims about their tests.

“The DTC model for offering tests has created public health and social quandaries, where tests that predict drug response, tests that predict serious future health risks, and tests that provide preliminary findings of genotype-phenotype associations are now available to persons ordering their own testing,” FDA wrote.

Many experts say genetic test kits give incomplete information, and any results about disease risk, especially for incurable diseases such as Huntington's or Parkinson's, should only be done with genetic counselling that clearly explains the limitations of genetic testing.

Testing companies, however, say the tests are useful for modifying bad habits that could contribute to future health risks, especially if someone is predisposed to a disease.

The FDA said genetic tests for consumers are similar in several ways to home use medical tests. But unlike those tests, many over-the-counter genetic tests have disclaimers stating that they are for “educational and informational” purposes and that the person getting the test results may want to follow up with a doctor.

FDA regulates home use tests, such as collection kits used to take samples of blood or urine that are sent to a certified labs to be interpreted. Often counselling is provided. It has also cleared several home use test kits for things like glucose, cholesterol and pregnancy tests.

Genetic tests, the agency says, “effectively create a third type of home use tests” in which follow-up is often left to the individual taking the test.

The agency says it does not intend to tackle doctor-ordered genetic tests in clinics or consumer genetic tests that do not make medical claims but are used to research family history or by law enforcement. It also will not address the prickly issue of how to safeguard consumers' personal information stored in DTC testing company computers. - Reuters

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