Alterations in SF3B1 have been reported in myelodysplastic syndromes (~20%)19, 42, 43, acute myeloid leukemia (~5%)19, chronic lymphocytic leukemia (~5%)12, 19 and other solid tumors including breast cancer (~1%)19, 20, 21, renal cancer (~3%)19 and adenoid cystic carcinoma (~4%)19. Here, SF3B1 is linked to breast cancer.