Splicing event signature separates SF3B1-mutated MDS cases. PCA plot based on the inclusion levels of the signature splicing events in the patient samples of Pellagatti et al,⁹  separating MDS SF3B1^K700E-mutated patients (K700E SF3B1mut MDS) and patients with SF3B1 mutations other than K700E (non-K700E SF3B1mut MDS) from patients without SF mutations (SF-WT MDS) and healthy individuals (WT). The asterisk marks 1 patient annotated as SF-WT. Clustering of this sample together with the SF3B1-mutated cases prompted us to more closely interrogate the sequence of the SF3B1 locus for any previously unidentified mutations. We thus discovered an in-frame 6-bp deletion (SF3B1p.K700_V701delKV) removing 2 amino acids, including the K700 hotspot.