UNG and urothelial carcinoma: These two mutation signatures frequently coincide in human tumors but can occur separately as reported for B-cell lymphoma cell lines, urothelial carcinomas with micropapillary histology, ApcMin colorectal tumors in A3A transgenic mice, and for yeast and human cells defective in uracil DNA glycosylase or the translesion DNA polymerase Rev111,15,34–37.