General miRNA expression patterns across normal and thrombocytotic cohorts. (A) Aggregate expression patterns are displayed for platelet miRNAs displaying > 70% present calls by cohort, in order of increasing fluorescence intensities. Expression data for each cohort represent normalized means from healthy controls (n = 30), ET (n = 27), or RT (n = 22). (B-D) Unsupervised hierarchical clustering was completed based on correlation proximity; miRNA expression data are standardized to mean = 0, SD = 1 before clustering, and displayed as a continuous data range from −4 to +4. ET cohorts are substratified by the presence (ET⁺) or absence (ET⁻) of JAK2^V617F. (B) The clustering dendrograms using the aggregate 392-member miRNAs, which demonstrates relative segregation of ET from RT and NO cohorts, whereas (C) ET and NO phenotypes alone and (D) all 3 phenotypes delineate the phenotypic segregation using the 21-member miRNA list. Note the relative continuum of phenotypes in panel D as defined by the 21-member miRNAs, exclusive of a small genetically heterogeneous subset (hatched box).