Genetic Testing, Antibiotic Resistance, and CLSI

So, in some quarters, there's been wailing and gnashing of teeth over the Congressional hearings about the direct-to-customer ('DTC') genetic testing industry. I've discussed why I don't think regulation is a disaster before, but I'll add one more issue to the mix: maintaining subject confidentiality in NIH genomic studies. If someone related to a person in a study publicly releases his or her genome, it could be possible to identify a 'deidentified' anonymous subject. I'm curious to see how that issue shakes out.

But that's not what this post is about. Instead, I propose that the DTC genetic testing industry should follow the path set by antibiotic susceptibility testing--the laboratory processes used to determine if bacteria are resistant to antibiotics.

First, the DTC industry has to realize that they are in the medical testing device business.

Like it or not, once they moved beyond vanity genomes for rich or well-connected white guys, and started to make medical claims, well, that makes genetic testing a diagnostic device.

Anyway, antibiotic resistance. A private organization, CLSI, sets the standards for determining resistance. And they specify everything down to the types of media and growth conditions for culturing bacteria, the 'breakpoints'--concentration of antibiotic that indicates resistance. They also certify labs by sending them panels of strains that are then tested by each lab to determine to which antibiotics they're resistant. This standardization is absolutely critical, and has improved clinical technique.

Genetic testing could the same thing: labs could be sent specimens and then these specimens would be tested. Both the data and the report to the customer would be evaluated. In addition, labs could be randomly tested to determine that they're not doing anything unethical, such as analyzing someone's DNA when they haven't given consent.

I'll admit this approach isn't perfect, as there is a lot of back and forth about what constitutes resistance. Drug companies typically want to lower the resistance thresholds for their competitors' drugs (thereby 'increasing' resistance to that drug) and increase the thresholds for their own drugs. But it still seems to work pretty well: we're not seeing massive amounts of deadly misdiagnoses due to poor resistance thresholds*.

By the way, while the largest antibiotic resistance susceptibility testing company is French (although they have expanded massively in the U.S.), the bulk of sales are to U.S. companies. Regulation hasn't 'killed' U.S. innovation.

One final note regarding the trouble Illumina is facing**. I can't understand for the life of me why Illumina didn't disassociate its testing business from its technology business. If nothing else, the potential for legal exposure alone should have resulted in this. Stupid.

*There is a separate issue, which is that people will respond differently to the same concentration of antibiotics, but it's not clear to what extent this has much to do with poor outcomes.

**Full disclosure: the center where I work uses Illumina sequencing technology as its primary sequencing technology.