While TET2 mutation occurs at near-equal frequencies in PTCL-GATA3 and PTCL-TBX21, DNMT3A, TET,1 and TET3 mutations were more commonly detected in PTCL-TBX21 [37]. The gene discussed is DNMT3A; the disease is mature T-cell and NK-cell non-Hodgkin lymphoma.