The splicing factor subunit 3b 1 (SF3B1) is amongst the most commonly mutated components of the splicing machinery, with high incidence in myelodysplastic syndromes (MDS; Je et al., 2013) and chronic lymphocytic leukemia (CLL; Miao et al., 2019). This evidence concerns the gene SF3B1 and B-cell chronic lymphocytic leukemia.