When screening and diagnosis converge: participant interpretations of additional findings in the 100,000 genomes project.

Genomic science is a central feature of the UK government's current 10-year health plan for England, which places significant emphasis on prediction and prevention. Although NHS prevention strategies have long been aimed at catching diseases earlier and at a more treatable stage, genomics until now has focussed largely on diagnosis and treatment. At present, there is limited evidence on how patients and publics engage with uncertain and probabilistic genomic information. While the public health benefits of this turn towards genomic screening may take time to establish, insights can be gained from recent large-scale diagnostic initiatives that also offered a screening element. This article draws on a qualitative longitudinal study of 100,000 Genomes Project participants, within which decision-making around the option to receive Additional Findings (AFs) was discussed. By focusing on future health risks in asymptomatic individuals, AFs can be understood as an opportunistic form of screening. Analysis identified three interrelated themes: ambivalence, reflecting anxiety and uncertainty surrounding decisions to receive AFs; inevitability and participant's own perceptions of patterns of future risk within families; and legacy, capturing motivations framed in collective and relational terms. Participants' accounts reflected enduring expectations of genomic medicine as a source of certainty and clarity, which sits uneasily alongside probabilistic and uncertain forms of knowledge such screening approaches are likely to produce. Understanding how individuals and families conceive of the potential and pitfalls of employing genomic tests in screening contexts is vital as a range of countries pilot or adopt genomic tools in population health services.