2006-09-01   Claudia Haferlach , Ulrike Bacher 

1.Department for Internal Medicine III, Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistr. 15, D-81377 Munich, Germany

Clinics and Pathology


BCR-ABL negative chronic myeloproliferative disorders (CMPD).


Occasional occurrence: 5 cases of polycythemia vera (PV) and one case of therapy associated AML (t-AML) after ET were reported so far.


2/5 PV cases showed conversion of PV to post-polycythemic myelofibrosis.


Probably associated with progression or leukemic transformation of the CMPD.


Cytogenetics morphological

Unbalanced translocation between chromosomes 9 and 18 leading to trisomy of 9p and monosomy of 18p.
Atlas Image
+9,der(9;18)(p10;q10) (chromosome painting, WCP#9 (red) + WCP#18 (green)).

Additional anomalies

Sole abnormality in most cases; balanced translocations or complex aberrant karyotypes were reported as additional abnormalities.

Genes Involved and Proteins

Genes involved are unknown. Gain of 9p might play a role for gain of function of the JAK2 gene on 9p24 which codes for the JAK2 nonreceptor kinase.


Pubmed IDLast YearTitleAuthors
126456492003Karyotypic abnormalities in myelofibrosis following polycythemia vera.Andrieux J et al
159932762005Gain of 9p due to an unbalanced rearrangement der(9;18): a recurrent clonal abnormality in chronic myeloproliferative disorders.Bacher U et al
96696701998Gain of 9p in the pathogenesis of polycythemia vera.Chen Z et al
158581872005A gain-of-function mutation of JAK2 in myeloproliferative disorders.Kralovics R et al


Atlas Image
+9,der(9; 18)(p10;q10) (G-banding).


Claudia Haferlach ; Ulrike Bacher


Atlas Genet Cytogenet Oncol Haematol. 2006-09-01

Online version:;18)(p10;q10)

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