Mutational processes in BL. (A) Mutation frequency is shown for each disease subtype. From top to bottom, the following SSMs are considered in each tumor: all genome-wide SSMs, SSMs outside noncoding mutation peaks, SSMs within peaks, and nonsynonymous SSMs in all protein-coding genes. This analysis was restricted to WGS data from the BLGSP discovery cohort (N = 91). (B) Number of BLGs that are mutated in each BLGSP discovery and validation case (N = 120). All mutation types were considered, as displayed in Figure 4. Discordant cases are highlighted as red points. The number of mutated BLGs was compared using Mann-Whitney U tests (**P < .001). (C) Estimated number of single-nucleotide variants is shown per mutational signature for each disease subtype in the BLGSP discovery cohort (N = 91). The 4 de novo mutational signatures (BL sig.) are annotated with the associated COSMIC reference signature (COSMIC sig.). ICGC cases were excluded to avoid the possible confounding effect of lower sequencing coverage. Significance brackets (panels A and C): *Q < 0.1; **Q < 0.001; ***Q < 0.00001 (Mann-Whitney U test).