Genetic testing by post
In the last few years, genetic testing has become more and more widely available outside of clinical and research settings. You could go online now and order a genetic testing kit with the click of a few buttons or you could pick one up at a local pharmacy. This is known as direct to consumer testing. These tests will give you information on things like ancestry or disease risks, or they could tell you how you might respond to certain drugs. Some offer whole genome sequencing, while others look at a smattering of genetic markers across the genome that might be of particular interest or have a known link to disease.
Advocates of this type of testing say that consumers should be able to independently access this risk information without having to go through a healthcare professional. Once people have this information they may be able to take beneficial steps such as seeking out treatment or changing their lifestyle.
So do these tests represent the ultimate liberation of genetic information or could they do more harm than good?
Many people have reservations about these direct to consumer tests. The US FDA (Food and Drug Administration), which regulates drugs and medical devices, has reviewed some direct-to-consumer test kits and stipulated what they can and cannot report. At present there is no such regulation in the UK, and concerns persist around the availability of genetic testing in the absence of genetic counselling or input from a physician.
Nowadays, some companies offering direct to consumer testing recommend that anyone having genomic testing seeks advice from a healthcare professional on receipt of results, while some offer counselling as part of their service. However, many companies continue to provide genomic testing without suggesting or offering counselling, and those that do offer support are not necessarily regulated in the same way as national healthcare bodies.
The lack of genetic counselling could have psychological implications for patients if they receive bad news based on their results; and this could potentially affect members of the family who could share a particular genetic risk factor. Genetic counsellors (health professionals specifically trained to provide genetic counselling) are also there to make sure patients understand the meaning of their results. Without this, there is a risk that an individual may overestimate their own risk or, conversely, be falsely reassured. For example, several direct to consumer testing companies offer BRCA1 and BRCA2 testing. As we learned in week one, there are many genetic variants in these genes that are linked to an increased risk of developing breast cancer. But a personal genetic test will usually only look at three of the most common variants. Therefore a negative test result does not exclude the possibility that someone has a BRCA1/2 risk allele.
Another question is whether the results of such genetic tests are actually useful. Many common diseases are the result of a complex interaction between multiple genes and the environment, rather than single genetic variants. What’s more, treatment may not be available for all diseases detected by the kits. For example, the APOE gene has been linked to Alzheimer’s disease (although not strongly enough to be recommended by the UK national health service for routine testing). However, there is currently no clear evidence that Alzheimer’s disease can be prevented. So, what can a person do with that information? Some genetic information can be empowering, but some could simply be a source of anxiety.
We also previously discussed the importance of trust and data privacy in research settings. However, the same safeguards are not necessarily in place for personal genomics companies. Some commercial companies allow access to third parties to consumers’ genetic and phenotypic data for research purposes. One company, which asks consumers to opt-in to this data sharing, previously made a deal with a biotech company for $60 million for access to their data.
There are many legitimate concerns and questions regarding direct to consumer testing. However, this is not to say that individuals have not, or will not, gain benefits from these tests. Their presence on the market means that genetic testing is available to people who might not otherwise have access to it - for example if they don’t meet certain criteria in a healthcare setting. And, many of these providers do encourage consumers to seek out genetic counselling, even if they do not offer this service themselves. If used responsibly and informatively, such tests could have a positive effect for patients. And, regardless of the issues raised above, the area of consumer genomics looks set to grow and grow as we become more and more interested – and knowledgeable – about genomes.