CDA and cancer: We used deconstructSigs (22) to infer mutational signatures in our cohort from whole-exome sequencing data and identified prevalent signals associated with DNA-editing activity of the AID/APOBEC cytidine deaminase family (signatures SBS2 and SBS13 in COSMIC, Fig. 2B), with APOBEC3A believed to be the main catalyser of such mutations in human cancers and a potentially more minor role from APOBEC3B (38, 39, 40).