This result was confirmed by RT-PCR in patient and healthy control HSC samples: the aberrant ABCB7 transcript was observed in all SF3B1-mutant MDS samples analyzed (n=7), but not in any of the samples from wild-type patients (n=4) or from healthy controls (n=5) (Figure 4a). Here, ABCB7 is linked to myelodysplastic syndrome.