Screening of mutations In collaboration with Department for clinical genetics, Uppsala, an initial screening of mutations will be performed using the commercial TrueSight© sequencing panel which includes 54 genes recurrently mutated in myeloid diseases. Based on the mutations identified, PCR-primers for all patient-specific mutations will be designed. Patients without any mutation will be excluded from the study. The mutational screen is performed as soon as a patient is being identified as a potential candidate for allogeneic stem cell transplantation (SCT) and evaluated for most optimal pre-SCT treatment. The patient is included in the study before the bone marrow sampling preceding SCT. In case a mutational screen has not been performed before pre-SCT MDS treatment, a mutational screen from the diagnostic national biobank sample (peripheral blood) can be performed.