TET2 and acute lymphoblastic leukemia: Reduced TET2 mRNA expression is an adverse prognostic marker in pediatric acute lymphoblastic leukemia (ALL), where low TET2 transcript in leukemic lymphocytes is associated with a significantly lower 5‐year OS (HR [95% CI] = 3.115 [1.42–6.81], p = 0.005) (Table 2) and EFS (HR [95% CI] = 3.49 [1.59–7.69], p = 0.002) (n = 130) [115].