IDH2 and angioimmunoblastic T-cell lymphoma: In support of the previous observations that TET2 and DNMT3A mutations occur at an early stage of haematopoiesis, and were seen in non‐neoplastic B and CD8+ T cells in patients with AITL 7, 13, 14, 15, 16, we found that the mutation allele frequencies of both TET2 and DNMT3A were significantly higher than those of RHOA and IDH2 (supplementary material, Figure S3).