IKZF1 and acute lymphoblastic leukemia: Whole exome sequencing (WES) revealed a large number of C > G transversions in 5AZA treated mice, including genes known to be important for ALL such as Chd4, Ikzf1, and Trp53. Single base substitution (SBS) profiling revealed increased C > G mutations in the ALL cells, with a mutation signature similar to the previously described SBS39 signature.