Classification of variants of reduced penetrance in high-penetrance cancer susceptibility genes: Framework for genetics clinicians and clinical scientists by CanVIG-UK (Cancer Variant Interpretation Group-UK)

Current practice is to report and manage likely pathogenic/pathogenic variants in a given cancer susceptibility gene as though having equivalent penetrance, despite increasing evidence of intervariant variability in risk associations. Using existing variant interpretation approaches, largely based on full-penetrance models, variants in which reduced penetrance is suspected may be classified inconsistently and/or as variants of uncertain significance. We aimed to develop a national consensus approach for such variants within the Cancer Variant Interpretation Group UK (CanVIG-UK) multidisciplinary network.