Common cytogenetic aberrations are monosomy 7 and trisomy 8, and somatic mutations in genes that encode epigenetic modifiers (e.g., TET2, ASXL1, EZH2), splicing factors (e.g., SRSF2, SF3B1, ZRSF2), transcription factors (e.g., RUNX1), and signaling genes (e.g., NRAS, CBL, KRAS, JAK2) are commonly found in CMML patients [5, 7–11]. This evidence concerns the gene JAK2 and chronic myelomonocytic leukemia.