Direct-to-consumer pharmacogenomic testing assessed in a US-based study.

Abstract

SUMMARY Direct-to-consumer genetic testing has been around for approximately 20 years. Pharmacogenomic testing is a specialised form of this testing which informs the risk of developing particular toxicities or showing a lack of response when prescribed certain drugs. These tests were widely available in the US via companies such as 23andMe 1 but, somewhat controversially, public access has been recently restricted by the US Food and Drug Administration (FDA). 2 More limited, but similar, testing is also available in the UK, though consumers are expected to speak to a ‘genetics trained’ advisor first. Bloss and colleagues conducted a study on participants in the Scripps Genomic Health Initiative (SGHI) involving more than 3,000 individuals from academic institutes and technology companies in California. The participants were offered subsidised commercial pharmacogenomic testing. The current study compares certain outcomes between participants who had received the results of pharmacogenomic testing (approximately 35% of 1325 study participants) and those who were still awaiting their results (approximately 65%). The outcomes compared included concerns about privacy, whether results were shared with family members and doctors and whether the participants availed themselves of further free genetic counselling. The group that had received results were slightly more likely to have visited their primary care physician and significantly more likely to plan to share their results with their doctor than the group still awaiting the results. After receiving the results, participants were also more likely to decide to seek genetic counselling. The 475 participants who had already received their results were subdivided into those at high (41 participants) and low (434 participants) pharmacogenomic risk, based on data they provided about medicines taken currently or previously. These groups were compared on a number of outcomes such as visiting their primary care physician or another healthcare provider and level of distress after receiving their results. The main findings were that those in the high risk group were considerably more likely to have visited their primary care physician after receiving the results and were slightly more likely than the low risk group to share their results with their doctor. They were also twice as likely as the low risk group to seek genetic counselling. Levels of satisfaction with the process, including finding the test results useful, understanding them and sharing results with both their family and their doctor, were high for participants who had received results. In particular, the group with test results was significantly more likely to consider the results useful and understand them compared with the expectations of the group still awaiting the findings. There was no evidence for any changes in psychological health or increased distress following release of results.