European citizens' perspectives on direct-to-consumer genetic testing: an updated systematic review

Background: Direct-to-consumer genetic tests (DTC-GTs) are genetic tests for a medical or non-medical trait that are sold directly to the public, usually ordered without the engagement of a healthcare professional. Our aim was to explore the knowledge, attitudes and behaviors toward DTC-GTs among European citizens. Methods: We updated the most recent systematic review on citizens' perspectives toward DTC-GTs. Relevant English language studies were searched on PubMed, ISI Web of Science, Scopus, Embase and Google Scholar from October 2014 to April 2019. We extended our search on Scopus without publication date restriction, since it was not included in the former review. Eligible studies were conducted in European countries and reported original data. The quality of the studies was evaluated using a checklist developed by Kmet et al. Results: We included six studies conducted in European countries between 2015 and 2018. The studies were performed among general population in the Netherlands, students in Italy and Greece, laypeople in Germany and older adults in Switzerland. The level of awareness, in overall low, differed by country and population group. Most of the participants were interested in undergoing a DTC-GT, mainly for knowing the risk predisposition to a common disease. Concerns were raised about tests' validity and utility and data privacy. Conclusions: Our review shows that European citizens, overall, have a low level of knowledge on DTC-GTs and a high interest in their purchase. This understanding might contribute to the development of educational programs in order to the increase of general public capabilities to make appropriate health decisions.