Recently, changes in the promoter methylation and gene expression of erythroid transcription factors (GATA1, KLF1, TAL1, JAK2, etc.), as well as factors implicated in protein binding (MEF2c, BRAF, RCOR1, LIFR, and CTNNA1), were observed in AEL mouse models. The gene discussed is KLF1; the disease is acute erythroid leukemia.