WT1 and Wilms tumor: We subjected blood and kidney DNA to whole genome sequencing (mean coverage 79X) and to methylation arrays, searching for pathogenic germline or mosaic DNA changes in established Wilms tumour predisposition genes (e.g., WT1), other cancer predisposition genes (e.g., TP53) and cancer genes generally, as per COSMIC (Supplementary Table 2)(13–18).