Mutational and copy number (CN) analysis of sorted PB subpopulations in patients with concurrent MPN/LPD. (A) Allele frequencies (%) of patient-specific variants in whole PB, unsorted PB MNCs, and PB subpopulations as determined by targeted sequencing (whole PB) or ddPCR (unsorted MNCs and sorted fractions). Mutation-positive fractions are shaded in gray, with the length of the bars proportional to the VAF. White squares indicate populations where variants were not detected. TET2 v1 (TET2 variant 1) refers to the TET2 L446fs variant; TET2 v2 (TET2 variant 2) refers to the TET2 H1219R variant. In patient C, the MPL W515L VAF exceeded 99% in the CD34⁺/monocyte fractions, consistent with the known loss of heterozygosity of chromosome 1p in this patient. (B) CN at the chromosome 13q14 locus as determined by ddPCR in unsorted PB MNCs and PB subpopulations from patient C as well as PB MNCs from 4 healthy controls (HC). CN measurements are depicted by a circle, with error bars indicating the 95% confidence interval.