The general public is increasingly interested in the promise of personal genomics for reasons ranging from health concerns to recreation. This is due to a convergence of web-based social networking and high throughput sequencing, leading to an “explosion” of DTC genomic companies in the past 5 years. Leading DTC companies market directly to consumers on company websites with slogan like “Gain insight into your traits, from baldness to muscle performance. Discover risk factors for 97 diseases. Know your predicted response to drugs, from blood thinners to coffee. And uncover your ancestral origins. All for $99 (was formerly $199)”. A gushing customer testifies regarding how “because he has given his doctor DNA information from 23andMe, he got his diagnosis much faster, and 23andMe saved my life.”
DTC genomics testing typically involves the submission of a convenient sample (usually saliva) by the consumer by direct mail to a CLIA-certified laboratory (owned or contracted by the DTC company) without a physician’s order. The sample is then tested for hundreds to millions of single nucleotide polymorphisms (SNPs), many of which have some association with diseases, responses to drugs or traits (phenotypes) that consumer might want to explore. Currently, except for a small percentage of genetic diseases, most SNP genomics information about gene-trait risk assessment has low predictive power and thus marginal clinical value. Additionally, risk prediction does not equate to diagnosis. For most common, multigeneic conditions, such as cancer, diabetes, and heart disease, genomic information is only a piece of the complex disease etiology and risk assessment puzzle. Even with these uncertainties consumers seek information as illustrated in a survey by Neumann et al. (1) which showed that 70-88% of the public is willing to pay for genomic tests even if results have no immediate clinical value or utility. Coupled with the trend of decreasing genomic testing costs and increasing sophistication of DTC companies’ marketing and advertisement, this will inevitably lead to more demand for DTC testing in the future. A report by the US Government Accountability Office highlighted the findings of testing by different DTC labs of the same donor samples produced different genetic results and interpretations, raising the issue of overall reliability or comparability of DTC genomic tests and interpretations. The design of the tests and the genetic variations detected by each company’s testing are not standardized and thus contribute to the lack of comparability of genotype and interpretations. A genetic expert consulted by GAO stated, "the fact that different companies, using the same samples, predict different directions of risk is telling and is important. It shows that we are nowhere near really being able to interpret [such tests]." In addition, several DTC companies being surveyed made deceptive marketing and fraudulent claims, e.g. the consumer DNA information can be used for “creating a personalized supplement to cure diseases” (2).
So is easier and greater access to one’s personal genome a good or a harmful practice? There are many questions that arise currently and no doubt you can think of others:
Because of these concerns, there is general consensus among academics and professional medical organizations calling for increased oversight and regulatory control of DTC genomics by the FDA. And the FDA has responded by issuing many letters to these companies calling for review and justification of the interpretation of their testing claims. What are your thoughts? If the cost for a whole genome profile drops to less than $500 would you pay to get your DNA tested by one of these DTC outfits?
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