Q&A With Scott Roberts, PhD: Direct-to-Consumer Cancer Gene Testing
In this question-and-answer session, Cancer Therapy Advisor asked Dr Roberts about direct-to-consumer genomic testing for cancer risk.
Scott Roberts, PhD, is an associate professor in the department of health behavior & health education and director of the Genomics, Health & Society Program at the University of Michigan's Center for Bioethics & Social Sciences in Medicine, Ann Arbor.
He studies genetic risk assessment effects for patients at risk for adult-onset diseases and is principal investigator of the federally funded Impact of Personal Genomics (PGen) Study.
Soon after the US Food & Drug Administration (FDA) approved 23andMe's direct-to-consumer (DTC) genomic testing for several non-cancer diseases, Cancer Therapy Advisor asked Dr Roberts about the PGen Study and the implications for DTC cancer risk testing in the future.
Cancer Therapy Advisor (CTA): What are the goals of the PGen Study and what is it revealing about DRC gene testing?
Dr Roberts: The PGen Study was a National Institutes of Health (NIH)-funded longitudinal survey of over 1800 consumers of 2 leading DTC genetic testing companies — 23andMe and Pathway Genomics. (Pathway has since switched to a physician-mediated model.) A recent publication of mine highlighted key findings on the risks and benefits of genetic testing in this format.1
On the positive side, the majority of consumers (59%) said their test results would be useful in managing their health moving forward and very few (1% to 2%) reported regret about seeking testing or harms from the experience. On the other hand, nearly 40% of consumers did not consider the potential for unwanted information from test results, suggesting a need for improved informed consent processes in this context.
Several other publications have resulted from this project:
- Consumers generally understand the key health implications of DTC genetic testing results, although such understanding varies by consumers' levels of numeracy and genetic literacy.2
- Genetic test results are not only of interest in predicting future risk of disease, but also in helping to explain medical conditions that consumers already have.3
- DTC genetic testing may be of special interest to adult adoptees, who often lack information about their family health history within their biological families.4
- DTC testing prompted 27% of PGen participants to discuss their results with their primary care providers, though with varying levels of satisfaction.5
- The likelihood of certain potential harmful responses to testing — such as overutilization of cancer screening tests and medication changes without physician consultation — was very low among study participants.6,7