SRSF2 (serine/arginine-rich splicing factor 2—chromosome 17q25.2) mutations are seen in patients with MDS, CMML, PMF and AML.60, 61, 62, 63 In MDS and PMF, these mutations are seen in ~15–20% of patients and are associated with a shortened OS and LFS.61, 63, 64 In CMML, the frequency of SRSF2 mutations is higher (~50%), and these mutations are associated with increased age, less pronounced anemia and a diploid karyotype.16 Mutational hot spots include P95L, P95H and P95R.16 Thus far, in CMML, SRSF2 mutations have not demonstrated an independent prognostic impact on either OS or LFS.7, 16, 65. Here, SRSF2 is linked to chronic myelomonocytic leukemia.