Interrogation of exome sequence datasets from the TCGA database showed that the frequency of mutations associated with the A3B mutational signatures was significantly higher for mutant p53 tumours compared with WT-p53 in breast (P = 2.07 × 10−6), lung (P = 2.53 × 10−8) and endometrial cancer (P = 0.048) (Figure 5G). Here, TP53 is linked to neoplasm.