Absolute number and relative proportion of wild-type and mutant neutrophils in CALR^MUT and JAK2^V617F ET patients tested prior to receiving any cytoreductive therapy. Each bar represents an individual patient and shows the total neutrophil count at the time of testing, as well as the derived absolute number of mutant-positive and wild-type neutrophils. The latter are calculated from the relative proportion of mutant-positive neutrophils, as given above the bar, and assumes that mutant-positive cells were heterozygous for the mutation (ie, the proportion of mutated cells is double the percentage of mutant alleles).