Counsyl differs from other direct-to-consumer genetic testing services, such as 23andMe and Navigenics, because it doesn't rely on Genome-Wide Association Study (GWAS) results. Concerns have been raised about these tests because GWAS results are novel and their interpretation is uncertain. In contrast, healthcare providers already provide the same kind of testing as Counsyl - carrier testing for monogenic diseases. In the UK, for example, it is available through NHS regional genetics services accessed via GPs and medical specialists. But, although this testing is available on the NHS, it tends to be on a case-by-case basis, with decisions about what to test for based on family history and ethnicity.
Counsyl's service provides much more information in a single test than the carrier testing provided by the NHS. Furthermore, the direct-to-consumer nature of Counsyl's testing leapfrogs the NHS. The NHS traditionally acts as a gatekeeper, limiting people's access to those tests thought to be most relevant. Such tests obviously raise several issues for individuals who take them and discover they are carriers. While they are not at risk of developing the diseases, their children are. The implications for future behaviour may be hard to ignore: if one knows one is at risk, do you require a future spouse to also take a test? Do you feel obliged to adopt technical solutions, such as prenatal screening of embryos and selective termination? Psychological research suggests such tests generate feelings of guilt and responsibility, and dilemmas for patients about whether to tell other family members that they too maybe carriers.
These feelings are, of course, generated by the single genetic tests currently available - it is not clear that testing for multiple genes would create significantly more problems for individual patients. But the tests currently available on the NHS include genetic counselling to ensure the patient understands the test and the information provided. In contrast, the direct-to-consumer version of the Counsyl test includes optional counselling, but does not require it. While Counsyl seems to rejoice in the American claim that 'genetic testing is a human right, not a luxury', conventional carrier screening has tended to be offered in a more cautious way. It is based on the view that the results of genetic tests can be complex and people may need help in getting to grips with what they mean.
For the NHS, direct-to-consumer genetic tests pose particular challenges. It is not clear what happens if an individual who has paid for a Counsyl test requires further help. Do GPs or specialist NHS genetic services have a duty to explain the results of the test? What are the funding issues if a couple who know they may be at risk of having a child with, for example cystic fibrosis, seek prenatal diagnosis and possible termination? The supporters of such tests would claim that their widespread use will save the NHS money in the long run, by ensuring that every baby born is free of diseases which are incurable and expensive to treat.
We should be cautious about claims that the Counsyl test heralds a new age of eugenics: individual testing, prenatal screening and termination have been around for over a decade for some conditions. The Counsyl test simply increases the number of diseases tested for and loosens professional oversight of people's access to such interventions. Whether or not this is a bad thing probably depends on your view of the value of the medical profession. At the same time, one can question the analogy Counsyl draws between their test and the long-running Tay Sachs programme in the Jewish community. It is likely the consequences of widespread testing in individualistic, socially disparate societies will be different from that in a closely-knit ethnic/religious community with strong internal social control.
If we know anything about how individuals and societies respond to the availability of genetic information, it is that they do so in unpredictable and unexpected ways.