{"entity":{"id":"tet2","kind":"target","name":"TET2","aka":["KIAA1546","tet methylcytosine dioxygenase 2"],"tldr":"TET2 is an enzyme that helps erase methyl marks from DNA so genes can be switched back on. Losing it is one of the commonest first steps toward blood cancer; mutant IDH blocks it indirectly, which is part of how ivosidenib works when it restores normal maturation.","summary":"TET2 (chromosome 4q24) is a dioxygenase that converts 5-methylcytosine to 5-hydroxymethylcytosine and on to 5-formylcytosine and 5-carboxylcytosine, the first steps of active DNA demethylation, and also recruits the O-GlcNAc transferase OGT to CpG-rich transcription start sites of active genes (UniProt Q6N021). The clonal-haematopoiesis pathway record lists TET2 with DNMT3A and ASXL1 among the mutations of clonal haematopoiesis of indeterminate potential, present in more than a tenth of people over 70 and progressing to myeloid neoplasm at about 0.5 to 1% a year. In OnCo it appears as the enzyme that 2-hydroxyglutarate from mutant IDH1 inhibits, so that ivosidenib restores TET2-dependent demethylation and differentiation, and as a mutation of the follicular helper T-cell lymphomas in which romidepsin is active.","asOf":"2026-09-22","links":[{"label":"HGNC HGNC:25941","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:25941"},{"label":"UniProt Q6N021","url":"https://www.uniprot.org/uniprotkb/Q6N021/entry"},{"label":"NCBI Gene 54790","url":"https://www.ncbi.nlm.nih.gov/gene/54790"}],"tags":["wave5-target"],"related":["ivosidenib","romidepsin","idh","dnmt3a"],"cancers":["aml","aml-idh","peripheral-t-cell-lymphoma"],"sections":[],"technologies":["epigenetic-drugs"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":["epigenetic-reprogramming","clonal-haematopoiesis","idh-2hg"],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Prevalence not recorded in this wave: HGNC and UniProt carry no positivity rates and no other source was consulted."],"provenance":{"editedBy":"OnCo content wave 5 (HGNC REST, UniProt REST, corpus drug and pathway records)","editedOn":"2026-09-22"},"symbol":"TET2","hgnc":"HGNC:25941","ensembl":"ENSG00000168769","uniprot":"Q6N021","entrez":"54790","biology":"Mutant IDH1 converts alpha-ketoglutarate to the oncometabolite 2-hydroxyglutarate, TET2 and histone demethylases lose activity, and blasts stop maturing; ivosidenib shuts off 2-HG production and TET2 regains activity (ivosidenib mechanism steps). TET2 itself has no drug in the corpus.","whereFound":["Clonal haematopoiesis of indeterminate potential","IDH-mutant AML (TET2 inhibited by 2-hydroxyglutarate)","Follicular helper T-cell lymphomas with TET2 and DNMT3A mutations"],"targetClass":"tumor-suppressor","prevalence":[]},"route":"/targets/tet2/","neighbours":{"drug":[{"id":"ivosidenib","kind":"drug","name":"Ivosidenib","route":"/drugs/ivosidenib/"},{"id":"romidepsin","kind":"drug","name":"Romidepsin","route":"/drugs/romidepsin/"}],"target":[{"id":"dnmt3a","kind":"target","name":"DNA methyltransferase 3A (DNMT3A)","route":"/targets/dnmt3a/"},{"id":"idh","kind":"target","name":"IDH1 / IDH2","route":"/targets/idh/"}],"cancer":[{"id":"aml","kind":"cancer","name":"Acute myeloid leukaemia","route":"/cancers/aml/"},{"id":"aml-idh","kind":"cancer","name":"IDH1- and IDH2-mutated acute myeloid leukaemia","route":"/cancers/aml-idh/"},{"id":"peripheral-t-cell-lymphoma","kind":"cancer","name":"Peripheral T-cell lymphomas (including cutaneous T-cell lymphoma)","route":"/cancers/peripheral-t-cell-lymphoma/"}],"technology":[{"id":"epigenetic-drugs","kind":"technology","name":"Epigenetic drugs (HDAC, DNMT, EZH2, IDH, menin, BET)","route":"/technologies/epigenetic-drugs/"}],"pathway":[{"id":"clonal-haematopoiesis","kind":"pathway","name":"Clonal haematopoiesis (CHIP)","route":"/pathways/clonal-haematopoiesis/"},{"id":"epigenetic-reprogramming","kind":"pathway","name":"Epigenetic reprogramming","route":"/pathways/epigenetic-reprogramming/"},{"id":"idh-2hg","kind":"pathway","name":"Mutant IDH / 2-hydroxyglutarate","route":"/pathways/idh-2hg/"}]}}