Brief Reports |
1 MLL, Munich Leukemia Laboratory, Munich;
2 Interdisciplinary Clinic for Stem Cell Transplantation, University of Hamburg, Hamburg-Eppendorf;
3 Diakonie-Krankenhaus Schwäbisch Hall, Schwäbisch Hall;
4 Kreiskliniken Günzburg-Krumbach, Günzburg;
5 Hematology Practice Germering, Germering;
6 Hematology & Oncology Practice, München;
7 Hematology Practice, Würzburg;
8 Hematology Practice, Passau;
9 Hematology & Oncology Practice, Duisburg;
10 Hematology & Oncology Practice, Ev. Diakonissenkrankenhaus;
11 Hematology & Oncology Practice and
12 Hematology & Oncology Practice, Münster, Germany
Correspondence: Susanne Schnittger, PhD, MLL, Munich Leukemia Laboratory, Max-Lebsche-Platz 31, 81377 Munich, Germany. E-mail:susanne.schnittger{at}mll-online.com
ABSTRACT
To further characterize JAK2 exon 12 mutations, we performed molecular screening in 409 patients with polycythemia vera or unclear erythrocytosis with unmutated JAK2V617. The frequency of JAK2exon12 mutations was 10/63 (15.9%) in PV but only 5/346 (1.4%) in the erythrocytosis cases. Nine different mutations including four new types (D544-L545del, H538DK539LI540S, H538-K539del, V536-F547dup) were detected. In 2 cases we found evidence for the presence of cells homozygous for mutated JAK2exon12. As this was the case in only 2/15 cases with JAK2exon12 mutations (13%) homozygosity seemed to be less frequent than in V617F-mutated polycythemia vera (69%) (p<0.001). There were more females than males in the group of patients with a JAK2exon12 mutation (10 vs. 5) compared to the group with wildtype JAK2 (132 vs. 262; p=0.012). Median age of onset was lower than in the V617Fmut controls (58.5 vs. 67.8 years, p<0.001). In conclusion, JAK2 exon 12 mutation analysis contributes to diagnostics in polycythemia vera or erythrocytosis.
Key words: JAK2 exon 12, PV, erythrocytosis, V617.