Participant perspective on the recall-by-genotype research approach: a mixed-method embedded study with participants of the CHRIS study.

Recall-by-genotype (RbG) research recruits participants previously involved in genetic research based on their genotype. RbG enables the further study of a particular variant of interest, but in recalling participants, it risks disclosing potentially unwanted or distressing genetic information. Any RbG strategy must therefore be done in a manner that addresses the potential ethical and social issues. As part of an RbG pilot on the penetrance of Parkinson's disease variants, we conducted an empirical mixed-method study with 51 participants of the Cooperative Health Research in South Tyrol (CHRIS) study to understand participant views on RbG research approach. Participants were disclosed the disease under investigation but not the individual variant carrier status. Results showed that participants filtered the information received through personal experience and enacted mechanisms to address the concerns raised by invitation by resorting to personal resources and the support provided by experts. While the non-disclosure of the Parkin variant carrier status was deemed acceptable, disclosing the disease under study was important for participants. Participant preferences for disclosure of the disease under investigation and the carrier status varied according to how the knowledge of individual carrier status was perceived to impact the participant's life. This study provided insights into participant response to the RbG research approach, which are relevant for RbG policy development. A suitable communication strategy and granular options addressing preferences for invitation in the original informed consent are critical for an ethically informed RbG policy.