The aberrantly methylated TET enzymes in HNSCC patients were studied by Misawa et al. (2018a), who reported lower expression of TET-1 and TET-3 in HNSCC, while methylation level of these genes was higher in cancer cells, suggesting that downregulation of TET-1 and TET-3 must have been associated with their promoter methylation. The gene discussed is TET1; the disease is cancer.