–Driving force for MDS development and evolution to AML–Typical driver mutations conferring clonal advantages affect the ASXL1, EXH2, IDH1, IDH2, KRAS, NRAS, and TET2 genes (76)–Such mutations can result in clonal hematopoiesis even before overt MDS and AML occurs (77)–Also, familial MDS forms require second hits (e.g., monosomy 7 in patients with GATA2 mutation or loss of heterozygosity in patients with RUNX1 mutations) (78, 79). Here, KRAS is linked to myelodysplastic syndrome.