Consumer-marketed genetic testing

An entry in The Scientist blog yesterday, Consumer genetic tests on trial (requires registration), discusses a recent Government Accountability Office investigation into claims by companies marketing genetic tests to consumers, noting that "the results appear to hit a pretty rich vein of snake oil."

Brendan Maher comments, "They bought genetic test kits from four companies and sent in a dozen fictitious profiles from the same two people... The test’s first iteration, which submitted dog, cat, and blank samples were sent back because they couldn’t be processed, but the second test did not reflect well on the four companies exposing at best their proclivity toward ambiguous reports and recommendations, to at worst the disparate prediction of disease risk that verges on diagnosis and the soliciting of overpriced supplements or “DNA-repair” pills that presumably do nothing."

The full GAO report, "Nutrigenetic testing: tests purchased from four web sites mislead consumers," is available online, as well as recent related Senate committee hearing transcripts.

A previous Scientist blog entry, Genomes in the supermarket, noted that the academic community concluded that nutrigenomic tests being marketed directly to consumers "weren’t ready for prime time." The Scientist also includes a deeper discussion of the past evaluation of these products, Dieting for the genome generation: nutrigenomics has yet to prove its worth. So
why is it selling?

A recent commentary piece in the Journal of the American Medical Association, The incidentalome: a threat to genomic medicine by Kohane, Masys, and Altman, discusses the broader implications of screening tests that may scan up to the whole genome. These authors point out potential serious problems with interpretation of results in the absence of knowledge of mediating factors such as family history or test characteristics such as sensitivity and specificity, rate of false positives, etc.