DNMT3A mutation is associated with increased age and adverse outcome in adult T-acute lymphoblastic leukemia

The prognostic implications of DNMT3A genotype in T-ALL are incompletely understood. We performed comprehensive genetic and clinicobiological analyses of T-ALL patients with DNMT3A mutations treated during the GRAALL-2003 and -2005 studies. Eighteen of 198 cases (9.1%) had DNMT3A alterations. Two patients also had DNMT3A mutations in non-leukemic cell DNA, providing the first potential evidence of age-related clonal hematopoiesis in T-ALL. DNMT3A mutation was associated with older age (median 43.9 years v 29.4 years, p