Figure 1.

Schematic diagram of the JAK2 gene structure. A: JAK2 protein contains JAK homology domains 1 through 7 (JH1-JH7) with the JH2 pseudokinase domain highlighted in black. The corresponding exon regions are also shown. All mutated residues in exons 12–15 discovered in this report are indicated with mutation hotspots labeled in red. B: Representative sequencing chromatograms of some novel mutations. R564L and G571S in exon 13, the deletion of entire exon 14, and L624P in exon 15 are shown. Positions of mutant nucleotides are indicated by arrowheads and deleted nucleotides by dots.