title: Impact of JAK2 V617F mutation on hemogram variation in patients with non-reactive elevated platelet counts.
abstract: BACKGROUND
  Non-reactive platelet counts elevation occurs mainly in myeloproliferative disorders (MPDs), which have been reported to be closely associated with JAK2 V617F mutation. Complete blood cell count (CBC) is essential in diagnosis of MPDs, however, the impact of JAK2 V617F mutation on the patients' hemogram variation remains not clear.
  
  
  METHODS
  JAK2 V617F mutation was detected by allele specific real-time quantitative fluorescence PCR (AS-qPCR).
  
  
  RESULTS
  Of the 402 non-reactive platelet elevating patients, JAK2 V617F mutation was detected in 222 (55.2%) patients. RBC counts, WBC counts, platelet-large contrast ratio (P-LCR), platelet distribution width (PDW) and mean platelet volume (MPV) were much higher in JAK2 V617F mutated patients, except platelet counts. In addition, when the patients were classified into subgroups by blood cell counts, it was found that JAK2 V617F mutation rate increased progressively with the increase of RBC counts and WBC counts, other than platelet counts. Furthermore, trilineage hyperplasia group showed highest JAK2 V617F mutation rate (93.26%), followed by the bilineage hyperplasia groups. Lastly, JAK2 V617F mutant allele burden was found much higher in polycythemia vera (PV) patients [median(P25-P75): 45.02%(35.12%-54.22%)] than in essential thrombocythemia (ET) patients [median(P25-P75): 28.23%(17.77%-41.66%)], and that it increased with WBC counts (r = 0.393, p = 0.000) and RBC counts(r = 0.215, p = 0.001), other than platelet counts (r = -0.051, p = 0.452). Further analysis revealed that in ET patients, JAK2 V617F mutant allele burden correlated with WBC counts and platelet counts positively, other than RBC counts, while in PV patients, it correlated with WBC counts and RBC counts positively, but not platelet counts.
  
  
  CONCLUSIONS
  JAK2 V617F mutation occurs frequently in patients with non-reactive elevated platelet counts. The presence of JAK2 V617F mutation has great impact on hemogram variation, including RBC counts, WBC counts, platelet parameters and lineage hyperplasia, but not on platelet counts. Besides, JAK2 V617F mutant allele burden affects the blood cell proliferation pattern.
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhou
authors.forename: Yuanxin
authors.initials: Y
authors.lastname: Ye
authors.forename: Shugen
authors.initials: S
authors.lastname: Zeng
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Mao
authors.forename: Xingbo
authors.initials: X
authors.lastname: Song
authors.forename: Binwu
authors.initials: B
authors.lastname: Ying
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Lu
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
authors.forename: Lanlan
authors.initials: L
authors.lastname: Wang
mesh_terms: D000483:Alleles; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000097:blood / Q000235:genetics; D053614:Janus Kinase 2 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010976:Platelet Count; D012189:Retrospective Studies
chemical_list: D053614:Janus Kinase 2