TET2 and leukemia: Recent works have shown that the absence of Dnmt3a or Tet2 in hematopoietic stem cells predisposes to leukemia formation (Yang et al., 2016; Rasmussen et al., 2015), but that restoring the expression of Dnmt3a after the leukemia had developed did not revert the phenotype (Yang et al., 2016).