MOLECULAR ALTERATIONS OF CALRETICULIN IN BCR-ABL, JAK2 AND MPLNEGATIVE MYELOPROLIFERATIVE NEOPLASMS (MPN)

OJEDA MARA J; BRAGOS IRMA ; CALVO KARINA L; PRATTI ARIANNA F

ROSARIO

Congreso; XVIII Congreso XXXVI Reunión Anual de la Sociedad de Biología de Rosario; 2016

Sociedad de Biología de Rosario

MOLECULAR ALTERATIONS OF CALRETICULIN IN BCR-ABL, JAK2 AND MPLNEGATIVE MYELOPROLIFERATIVE NEOPLASMS (MPN)Ojeda M,Bragós I, Carbonell M, Williams G, Calvo K, Pratti ,Cátedra y Servicio de Hematología. Fac. de Cs. Bioq. y Farm. Universidad Nacional de Rosario. Suipacha 531 S2002LRK Rosario.Argentina. E-mail: mojeda@fbioyf.unr.edu.ar.We investigated the presence of mutations in exon 9 of the CALR gene in patients with ET (Essential Thrombocytemia) and PMF(Primary Myelofibrosis), JAK2V617F, MPLW515L/K negative. We studied genomic DNA from 44 patients diagnosed with ET (36)and PMF (8) according to WHO criteria. The methodology used was PCR amplification of exon 9 of the CALR gene from peripheral bloodor bon e marrow leukocytes, followed by automatic sequencing. Seven different mutations were detected in exon 9 of CALR in 63.6% ofpatients with ET and PMF JAK2 / MPL negative. The type 1 mutation (52 bp deletion) and the type 2 mutation (5 bp insertion) accounted for42.9% and 39.3% of the positive cases respectively. Of the 5 remaining mutations, only one case of each was found. 75% of patients with PMFhad mutations in CALR, being the most frequent type 2 mutation (83.3%), the type 1 mutation represented 16.7%. In the patients with ET,these mutations were present in 61.1% of the cases, the most frequent being mutation type 1 (50%). The mutation type 2 was found in27.3%, whereas the 5 types of remaining mutations had very low frequency since they were detected in a single patient each. The majority ofpatients with n egative JAK2 PMF and ET showed a mutation in the exon 9 of CALR, therefore the detection of these mutations is a veryuseful diagnostic tool to discriminate a clonal proliferation of a reactive process.