The authors discovered that ten-eleven-translocation enzymes (TET: TET1, TET2, TET3), originally considered as chromosomal translocations of the genes MLL and LCX (t(10;11)(q22;q23)) in acute myeloid leukemia patients [12,13], are actually responsible for changing the DNA methylation pattern [14]. This evidence concerns the gene TET1 and acute myeloid leukemia.