Comparison of gene expression in tumours with any of the 44 APOBEC-associated mutations to tumours devoid of them revealed that APOBEC3A and APOBEC3H were significantly upregulated in the mutated group, suggesting that the proteins encoded by these two genes might act as mutagens in tumours harbouring an APOBEC-associated mutation (Additional file 3: Fig. S5). This evidence concerns the gene APOBEC3H and neoplasm.