Taken together, these data are consistent with the CSDE1C-T mutation, which has a typical mAPOBEC3/APOBEC3B signature (TTCA-TCCA)11,14,48, being induced through Type I IFN induction of mAPOBEC3/hAPOBEC3B activity10,11 at a high clonality in VSV-IFNβ ESC cells across species and tumor types (Supplementary Fig. 1). Here, IFNB1 is linked to neoplasm.