Since concomitant SRSF2 and TET2 mutations can also be found to a certain degree in other MDS subtypes [13, 34], the mutation profile does not define a diagnosis on its own and has to be evaluated in the context of the clinical findings (e.g., sustained monocytosis ≥1000 μl−1, ≥10% monocytes) and morphological features (e.g., dysplastic features in at least one cell lineage). The gene discussed is SRSF2; the disease is myelodysplastic syndrome.