JAK2V617F allele burden decrease in patients achieving >25% reduction at 60 months and details of patients attaining complete molecular remission. (A) The percentage decline over time (mean ± SD) of the JAK2V617F allele burden in the 13 patients who presented a >25% allele burden reduction at 60 months. JAK2V617F allele burden decreased by a mean of 7%, 11%, 19%, and 28% at 1, 2, 3, and 5 years, respectively. (B) The absolute level of JAK2V617F allele burden in the 3 patients (pt) who finally achieved a CMR at 5 years (confirmed 3 months later) is presented. Measurement of the JAK2V617F allele burden was performed in peripheral blood granulocytes by RT-qPCR. The attainment of CMR was further confirmed by both a high-sensitivity RT-qPCR assay (detection limit, 0.08%) and deep resequencing at 5 years and at +3-month time points. SD, standard deviation.