Olivier LaRochelle 1* , Sarah Bertoli 2* , Francois Vergez 1,3* , Jean-Emmanuel Sarry 3 , Veronique Mansat-De Mas 1,3,4 , Sophie Dobbelstein 1 , Nicole Dastugue 1 , Anne-Claire Strzelecki 1 , Cindy Cavelier 1 , Laurent Creancier 5 , Arnaud Pillon 5 , Anna Kruczynski 5 , Cecile Demur 1,3 , Audrey Sarry 2 , Francoise Huguet 2 , Anne Huynh 2 , Christian Recher 2,3,4* and Eric Delabesse 1,3,4* 1 Laboratoire d’Hematologie, CHU de Toulouse, Hopital Purpan 2 Service d’Hematologie, CHU de Toulouse, Hopital Purpan, 31059 Toulouse, France 3 INSERM UMR1037-Cancer Research Center of Toulouse, CNRS ERL 5294, Pavillon Lefebvre BP3028, CHU Purpan, 31024 Toulouse, France 4 Universite Toulouse III Paul Sabatier, Toulouse, France 5 Centre de Recherche et Developpement Pierre Fabre, 3 avenue Hubert Curien, BP 13562, 31035 Toulouse Cedex 1, France * These authors contributed equally to the work Received: November 1, 2011; Accepted: November 1, 2011; Published: November 9, 2011; Keywords: DNMT3A, acute leukemia, idarubicin, NOD/SCID, xenograft Correspondence: Eric Delabesse, email: // // Abstract Mutations in DNMT3A encoding DNA methyltransferase 3A were recently described in patients with acute myeloid leukemia. To assess their prognostic significance, we determined the mutational status of DNMT3A exon 23 in 288 patients with AML excluding acute promyelocytic leukemia, aged from 18 to 65 years and treated in Toulouse University Hospital. A mutation was detected in 39 patients (13.5%). All DNMT3A exon 23+ patients had intermediate-risk cytogenetics. Mutations significantly correlated with a higher WBC count (p