[Image from 23andme.com]
The company 23andMe
offers a different kind of ‘tech’ than I usually talk about on this blog, but it is meant to be a useful service for you (and for the company to collect information across many individuals). Give them $100, and they will mail you a ‘spit kit’ with a tube that you literally spit in and send to it to them for analysis. They then use genotyping
to determine whether you have certain variations in your DNA that are associated with your ancestry
, disease, and other potentially genetically-derived traits.
I personally used their services about a year ago, mostly interested in ancestry. Honestly, I wasn’t too interested in their disease associations (though I believe this will become more and more useful as we sequence more individuals and develop better computational/statistical methods to analyze the data). In the scientific community, genetic associations with diseases are still, for good reason, met with skepticism (see, for example, this recent article). This skepticism has worked its way up to politicians, resulting in various efforts to regulate laboratory developed tests. I believe genetic testing and screening has a lot of potential and am excited that so many efforts exist to provide individuals with these kind of services, but as many scientists would probably agree, we are just beginning to understand how complex traits and diseases are associated with genetic variations across individuals.
23andMe recently received a letter from the FDA to “immediately discontinue marketing the PGS [Personal Genome Service] until such time as it receives FDA marketing authorization for the device”.
What surprised me when reading the letter was this statement:
Some of the uses for which PGS is intended are particularly concerning, such as assessments for BRCA-related genetic risk and drug responses (e.g., warfarin sensitivity, clopidogrel response, and 5-fluorouracil toxicity) because of the potential health consequences that could result from false positive or false negative assessments for high-risk indications such as these. For instance, if the BRCA-related risk assessment for breast or ovarian cancer reports a false positive, it could lead a patient to undergo prophylactic surgery, chemoprevention, intensive screening, or other morbidity-inducing actions, while a false negative could result in a failure to recognize an actual risk that may exist.
Perhaps because I have training in computational biology, I always assumed this information is meant to be more like a ‘hint’ or ‘suggestion’ that you might want to investigate a medical issue further with a physician who can conduct specialized follow-up tests and recommend further courses of action. For instance, I have a minor version of Beta-thalassemia that apparently doesn’t require medication or affect my daily activities. 23andMe correctly identified that I have this trait. This disorder can be discovered via blood testing by a physician, so if I didn’t already have these tests, my 23andMe report may have alerted me to investigate this further. I think this is useful information.
My 23andMe page also displays this disclaimer:
The genotyping services of 23andMe are performed in LabCorp’s CLIA-certified laboratory. The tests have not been cleared or approved by the FDA but have been analytically validated according to CLIA standards. The information on this page is intended for research and educational purposes only, and is not for diagnostic use.
I do think that it could be made more prominent perhaps with a clause that states that some of these associations are in a stage of ‘early research’, but I am writing this post more to pose a general question to anyone that has some insight into the legal aspects of this recently newsworthy topic: why isn’t the disclaimer above (or a better one) good enough for the FDA? Certainly, I understand that the general public doesn’t have the same knowledge I do about genetic tests, but given a disclaimer like this, why can’t 23andMe sell me their services and let me make follow-up decisions?
Some FDA links that are relevant: