IDH2 and myelodysplastic syndrome: It was of note that a series of clones were emerged or increased from the seven transformed CMML cases in our study, including FLT3, NPM1, IDH2, DNMT3A et al. Some newly acquiring mutations, the so-called type 1 mutations FLT3, NPM1, and IDH2, seemed to predict a much shorter time for disease progression from MDS to sAML than type 2 mutations that were present in MDS [41–44].