Identification of JAK2 (V617F) Mutation in Myeloproliferative Neoplasms by Using Allele Specific Polymerase Chain Reaction (AS-PCR)

Myeloproliferative neoplasms (MPNs) are a group of clonal haematopoietic stem cell disorders characterized by the proliferation of one or more myeloid cell lineages. According to WHO classification, the Janus associated kinase 2 (JAK2) V617F mutation is one of the major diagnostic criteria in BCR-ABL1 negative myeloproliferative neoplasms. The aim of this study is to detect the JAK2 (V617F) mutation in patients with myeloproliferative neoplasms to get accurate diagnosis and proper management. A total of 90 clinically diagnosed MPN patients attending to Department of Clinical Haematology, Yangon General Hospital were enrolled in this study. The mean age was 53.4 ± 14 years which ranged from 16 to 81 years old and male and female ratio was 2.4:1. The identification of JAK2 (V617F) point mutation was found to be positive in 44/90 MPN patients (48.9%). According to MPN subtypes, the JAK2 mutation positivity was found in 19 out of 46 polycythemia vera patients (41.3%), 17 out of 25 essential thrombocythemia patients (68%), 8 out of 15 primary myelofibrosis patients (53.3%), 0 of 4 others myeloproliferative neoplasms (0%). Confirmation of each of nine JAK2 mutation positive and negative samples was done by Sanger sequencing. The arterial or venous thrombotic attack was found in 32/44 JAK2 mutation positive cases (72.7%) and 12/44 JAK2 mutation negative cases (27.3%). The association between thrombotic attack and presence of JAK2 mutation was statistically significance with p = 0.000. The diagnosis of myeloproliferative neoplasms mainly relies on the molecular genetics according to WHO classification. The Allele specific PCR reaction is sensitive, simple test and relatively cost-effective. Therefore, the identification of JAK2 (V617F) somatic point mutation by AS-PCR should be implemented as a routine diagnosis procedure for patients with chronic and suspected myeloproliferative neoplasms.