ERBB2 and breast carcinoma: Moreover, these large public datasets have also enhanced our understanding on the divergent mutation accretion processes; most notably in breast cancer, studies have shown high APOBEC (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like)-related mutagenesis, especially in HER2 + tumors16, whereas BRCA1/2 mutations are strongly associated with signatures depicting DNA repair deficiency17.