Full 23andMe report back in the UK; is that controversial?
Last week, it was announced that the 23andMe genetic test is “now available to UK customers”. The news was reported with the headlines focusing on the idea that the UK might be too relaxed and less careful than the US on controlling direct-to-consumer genomic companies: DNA-screening test 23andMe launches in UK after US ban, Controversial DNA test comes to UK, Google-Backed Home DNA Screening Banned In America Comes To The UK.
Why is This Test Considered Controversial? Was it Really Banned?
I took the test myself last year, just before the US Food and Drug Administration (FDA) imposed the ban, and I have been following the story as it evolved. Many of my colleagues working in the field of human genetics also took the tests, probably for similar reasons. First of all I i) was curious, ii) wanted to easily access my own data and iii) wanted to take part in research. I never intended seriously to take a health test and I was not attracted by the idea of tracing back my ancestry and linking up with far away family members, which are other common reasons for taking the tests. Many adoptees have used it to trace their natural parents or siblings. The 23andMe database matches your own DNA with other customers who opted in for this option making it possible to discover a long range of relatives. Of course, by testing your own DNA, inevitably you are also going to discover the ancestry of your family members. As a result some people were happily reunited and in extreme cases the revelation of untold secrets broke families apart.
Privacy of course is an important issue, but I would not worry if somebody could get hold of my genetic information. They could figure out my hair and eye color and even my earwax type, but they would probably get more useful information by looking at my Twitter account and my supermarket card points as Ewan Birney, Associate Director of the EMBL-European Bioinformatics Institute (EMBL-EBI), who also took the test, said on Newsnight.
These are not reasons for the ban. In fact the test had not been banned completely but 23andMe have been prevented since November 2013 to advertise it as a health test and to provide customers with health reports. The news of last week is that costumers in the UK can now obtain the full report, including health entries, as every customer did before November 2013.
Because I did not complete the test to discover health information I would have still taken the test under the current ban.
What Health Information Can You Get From the Test?
The health reports are actually a bit meaningless. Each report is marked by a confidence level indicating to what extent one particular genetic variant confers risk towards or protection against disease. The high confidence entries are not many and I checked with a bit of trepidation only two of them; Alzheimer’s disease and breast cancer, both diseases running in my family. Not carrying risk factors, of course, is good news, but it only tells I am not a carrier of certain risk factors and I can still develop the diseases.
Most reports are low confidence and do not provide any real information. For example, the report for dyslexia is based on a single genetic marker. Having worked in the field of dyslexia genetics for quite a long time I can tell you that you cannot really predict the risk of developing such condition by looking at single marker with a very tiny effect size; the same applies for many other conditions.
Various rare and severe conditions are also included. In this case if you are healthy you probably do not have the condition, but you could be a carrier of a high risk variant. This information could be relevant for couples planning to have children. If 23andMe picks up one of these variants in both parents, than the couple would probably like to discuss their options with a clinician. Again, negative results in both parents cannot guarantee the baby will be healthy, simply because the 23andMe tests only for some known variants but does not exhaust all risk factors. The test also provides predictors of how one individual genetic background might affect drug response. A positive finding might be useful in establishing more effective medications.
The FDA ban is exactly about these reports to avoid people using 23andMe as a substitute for health checks. 23andMe explains pretty well on their reports the implications of their results but it is easy to see how the results could be over-interpreted. The question is whether 23andMe provides clear enough information for a lay audience to be able to interpret the results correctly and whether it is appropriate to promise the health reports when advertising the product. 23andMe has promised to address the FDA concerns and we will soon know if an agreement can be found in the US regarding the health reports.
In the meantime people have continued doing the test, including in the US, and taking part in research, which probably was my strongest motivation. Genetic screening is effective if sample sizes are big (in the range of tens of thousands). 23andMe has already contributed interesting research, such as to the recent discovery of risk factors for Parkinson’s disease. I would be thrilled by the idea that I could be one of the participants in a study that has contributed to important findings.
The Bottom Line
So, if you were going to get yourself, a friend or a relative a 23andMe genome screen this Christmas but have been put off by the controversies discussed in the media, here is my take. There is nothing to be scared of, but it is important to read all the information that comes with each component of the test. As long as you don’t consider 23andMe a substitute for a secure and comprehensive health check, it can be a fun way to learn about human genetics and maybe to contribute to scientific knowledge… Other people might have very valid points to advise against the test, but my view in this case is that knowing is better than not knowing.