The spectrum of mutations substantially overlapped with that of overt hematologic neoplasms—in particular, myelodysplastic syndromes (MDSs) and myeloproliferative neoplasms (MPNs)—with the epigenetic modifier genes DNMT3A, TET2, and ASXL1 and the tyrosine kinase gene JAK2 being most frequently mutated [4]. The gene discussed is TET2; the disease is myeloproliferative neoplasm.