“…JAK2 is a member of the Janus family of cytoplasmic non-receptor tyrosine kinases. A guanine-to-thymidine substitution, which results in a substitution of valine for phenylalanine at codon 617 of JAK2 (JAK2V617F), is responsible for the constitutively activity of this tyrosine kinase that activates signal transducer and activator of transcription (STAT), mitogen activated protein kinase (MAPK) and phosphotidylinositol 3-kinase (PI3K) signalling pathways, and transforms haematopoietic progenitor cells [ 14 - 16 ]. The discovery of JAK2V617F has led to the development of selective JAK2 inhibitors for the treatment of PV, ET and PMF (6, 16).…”