Recurrent somatic mutations of splicing factors (SFs) are implicated in splicing deregulation and are linked to hematologic malignancies (i.e., myelodysplastic syndromes (MDS) [7], chronic myelomonocytic leukemia (CMML) [8], and chronic lymphocytic leukemia (CCL) [9]), and some solid tumors (e.g., breast cancer and uveal melanoma [10]). Here, SLU7 is linked to chronic myelomonocytic leukemia.