Specifically, TET2 mutation was associated with an unfavorable OS in AML patients under 65 years of age (HR [95% CI] = 1.310 [0.999–1.718], p = 0.051) and in patients with normal cytogenetics (HR [95% CI] = 2.034 [1.440–2.872], p < 0.001) or intermediate risk cytogenetics (HR [95% CI] = 1.662 [1.312–2.105], p < 0.001). The gene discussed is TET2; the disease is acute myeloid leukemia.