title: JAK2-V617F mutation analysis of granulocytes and platelets from patients with chronic myeloproliferative disorders: advantage of studying platelets.
abstract: There have been conflicting reports over the JAK2-V617F mutation status of platelets in chronic myeloproliferative diseases (CMPDs). The aim of this study was to analyse JAK2-V617F status, not only in granulocytes but also in platelets. The JAK2-V617F mutation was analysed in both granulocytes and platelets in 115 patients with CMPDs using direct sequencing. JAK2-V617F was detected in granulocytes from 71 of those patients, all 71 of whom also had platelet JAK2-V617F expression. The remaining 44 patients showed negative JAK2-V617F expression on granulocytes, but positive JAK2-V617F expression was detected on the platelets from nine of the 33 essential thrombocythaemia (ET) patients, one of the eight polycythaemia vera patients, and two of the three primary myelofibrosis patients. When ET patients were divided into three groups according to granulocyte and platelet JAK2-V617F status (both-positive, platelets-only positive and both-negative), the both-positive and platelets-only positive groups shared the clinical features of higher white blood cell count and frequent thrombosis. These results suggest that analysis of platelets is a more sensitive approach for detecting JAK2-V617F in CMPD patients than analysis of granulocytes. They also suggest that previous reports of the incidence of JAK2-V617F in CMPD patients, obtained using only analysis of granulocytes, could be underestimations.
authors.affiliation: Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Gunma, Japan.
authors.forename: Kohtaro
authors.initials: K
authors.lastname: Toyama
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Karasawa
authors.forename: Arito
authors.initials: A
authors.lastname: Yamane
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Irisawa
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yokohama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Saitoh
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Handa
authors.forename: Takafumi
authors.initials: T
authors.lastname: Matsushima
authors.forename: Morio
authors.initials: M
authors.lastname: Sawamura
authors.forename: Shuichi
authors.initials: S
authors.lastname: Miyawaki
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Murakami
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Nojima
authors.forename: Norifumi
authors.initials: N
authors.lastname: Tsukamoto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000201:enzymology*; D002908:Chronic Disease; D004252:DNA Mutational Analysis; D005260:Female; D006098:Granulocytes / Q000201:enzymology; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D009154:Mutation; D009196:Myeloproliferative Disorders / Q000201:enzymology* / Q000276:immunology; D011087:Polycythemia Vera / Q000201:enzymology / Q000276:immunology; D055728:Primary Myelofibrosis / Q000201:enzymology / Q000276:immunology; D012306:Risk; D018709:Statistics, Nonparametric; D013601:T-Lymphocytes / Q000201:enzymology; D013920:Thrombocythemia, Essential / Q000201:enzymology / Q000276:immunology; D013927:Thrombosis / Q000201:enzymology
chemical_list: D053614:Janus Kinase 2