Within the major component, the SF3B core unit is comprised of spliceosome associated proteins including SF3B1 (Splicing Factor 3b Subunit 1), U2AF1 (U2 Small Nuclear RNA Auxiliary Factor 1), and SRSF2 (Serine And Arginine Rich Splicing Factor 2) that have been implicated in large a number of malignancies [6] including chronic lymphocytic leukemia (CLL) [7], uveal melanoma [8], and myelodysplastic syndrome [9]. The gene discussed is U2AF1; the disease is B-cell chronic lymphocytic leukemia.