TET mutations are linked to diseases, inter aliahematopoietic malignancies such as chronic lymphocytic leukemia (CLL),acute myeloid leukemia (AML), and chronic myelomonocytic leukemia(CMML).28−30TET2 is among the most frequentlymutated genes in myeloid neoplasms and inactivating TET2 mutants are linked to DNA hypermethylation, tumor progression, andpoor patient outcome. The gene discussed is TET2; the disease is B-cell chronic lymphocytic leukemia.