CHEK2 and leukemia: Fusion transcripts can generally lead to at least four different situations: (a) increased overexpression of an oncogene (e.g. IgH-MYC in leukemia), (b) deregulation of a tumor suppressor gene (e.g. CHEK2-PP2R2A in childhood teratoma), (c) generation of a new aberrant protein (e.g. BCR-ABL1 in leukemia), and (d) a combination of various of the above (e.g. MYB-QKI in angiocentric glioma)47,58.