Genetic testing is currently available for more conditions than ever and with greater precision.
Testing is so widespread, even affordable, that it has become a commodity with companies offering kits for gathering saliva, which are then mailed back, analyzed, and followed up with genetic reports. The technological ability to pore over one's genes dovetails with a zeitgeist promoting choice, knowledge, and patient autonomy. And what better proof to the marriage of zeitgeist and science than the name "The First Annual Consumer Genetics Show" which took place in Boston last week.
Understanding the genetic foundation of diseases is key not only to treatment but also to prevention. Such information is beneficial on a personal level, sometimes allowing people to counteract risk factors, or at least to prepare for what awaits them. Greater benefit still comes at an aggregate level, when more and more information is gathered about the interaction of genetics, behavior and environmental factors, and how these affect disease.
Yet it is doubtful that curious clients are aware of the emotional and potential judicial issues that may arise once they have relinquished their body fluids. Or that their physicians know how to interpret the new knowledge, let alone how to act upon it.
While ‘consumers' is a neutral word, granting one choice and material power, ‘patient' takes us to another domain. And, seeing as what lurks within our genes is often cause for worry, some consumers of genetic testing will be purchasing the knowledge that they are at greater risk than others to become patients. This may be good, in the case of conditions where one can be proactive in preventing disease onset, or improving prognosis. But what happens when this is not the case? Dr. Robert Green of Boston University, currently a Harvard Fellow of Genetics, related a study which did a follow up on people who were diagnosed as having the ApoE-ε4 gene associated with Alzheimer's disease. Alzheimer's, he said, offered a unique model for exploring clinical utility, as the analytic validity of the gene detection was excellent, and the clinical validity was well documented. On the downside for patients were the fact that no treatment could be offered, though this meant that pharmaceutical companies had no vested interest in promoting diagnosis. Despite the fact that no cure was in view, people wanted to know their risk. Most, though not all of the people who said they would participate in the study actually showed up. Initially, those who learned they had the risk factor gene were more distressed than others, but the effect wore off with time. This is also predicted by psychological theories of adaptation. Two things which future consumers of testing should note were that patients who had the ApoE-ε4 gene and who had the opportunity to speak with a counselor about the implications were less distressed than people who only got a brochure.
This suggests that when shopping for testing, one needs to find out not only the price and the range of mapping, but also what kind of support they would get once they hear the results. Dealing with genetic testing results demands more than cognitive skills. Adrian Edwards of Wales's Cardiff University recently reviewed studies on communication and decision aids in traditional oncological genetics. Edwards and his colleagues found that users gained improved understanding, knowledge, and risk perception from various interventions without adverse effects on anxiety, worry and depression. However, it was often the supportive or emotional elements of the counseling that provided benefits to users, rather than the informational or educational elements. Therefore, the availability of such support becomes an important issue for the consumer.
Do patients, I mean consumers, know they need to inquire on the quality of support? As Dr. Peter Ubel suggests in Free Market Madness, http://www.peterubel.com/free-market-madness/ people do not always act upon their best interests. And this might be one of these cases. As companies vary wildly in the degree of pre and post-diagnosis interpretation and emotional assistance they propose.
Another thing to be noted by future consumers, is thatpatients who were diagnosed as having the ApoE-ε4 gene were more likely to consume nutritional supplements several weeks after being diagnosed. While supplements are relatively cheap and harmless, this attests to the difficulty of being helpless when facing a terrifying disease prospect, and helplessness is perhaps exacerbated in individuals who are proactive to begin with.
Kenneth Kornman of Interlukin genetics spoke of the challenge companies face - how to responsibly deliver. This involves setting realistic expectations - clarifying that tests provide predictive risk assessment, but are not diagnostic, and acknowledge that we never have perfect information about the risk for future disease, and that while genetics are one well-defined component of disease, diseases are characterized by a combination of genes and risk factors. The same gene variant can be associated with either high or low ‘good' cholesterol levels, depending on the person's level of dietary fat.
Yet my studies show that people do not always understand probabilistic risk assessment, and that they sometimes expect more from genetic tests than the tests can deliver. For example, my colleagues and I asked women how important it was for them that screening for a gene associated with breast cancer would tell them with certainty whether they will develop breast cancer. Half the women answered "the test cannot do that", and they were right, because the test only offers a probability, not certainty. But a third of the women assigned great importance to this feature, which the test does not have.
So are direct to consumer genetics good or bad for you? And how does it relate to the Field of Dreams? More in the next posting.
