TET2 and acute myeloid leukemia: TET2 was shown to be frequently mutated in adult AML (8–28%) as compared to childhood AML (1–7%) (Langemeijer et al., 2011; Weissmann et al., 2012; Cancer Genome Atlas Research, 2013; Liang et al., 2013; Kao et al., 2014; Kutny et al., 2015).