Even though we have previously described statistically higher WBC and neutrophils in the double mutant JAK2-V617F/R1063H ET patients [14], the effect on granulocytosis in these patients could be caused by cumulative effect on JAK2 signaling of the two JAK2 (germline R1063H and somatic V617F) mutations. This evidence concerns the gene JAK2 and Increased total granulocyte count.