Unsupervised hierarchical clustering pattern of expression data. Each row represents a single transcript, and each column represents a single sample. Red represents greater expression; green, lower expression; and gray, missing data. In the sample dendrogram, red represents self-limited acute ITP samples; blue, chronic ITP samples; and green, normal controls. (A) Unsupervised clustering of self-limited acute and chronic ITP samples using the transcripts with significantly elevated expression in chronic ITP at the SAM q value of 0 (using clones corresponding to putative genes and > 80% good data, 57 biosequences passed the filters). Two distinct clusters of samples are revealed: the one on the left contains predominantly chronic ITP samples, whereas the one on the right contains only self-limited acute ITP samples. (B) Unsupervised clustering of self-limited acute ITP, chronic ITP, and healthy controls using the same set of transcripts and the same filter settings (57 biosequences passed filters). The expression level of these transcripts presented a low-to-high gradual transition from normal to chronic ITP. While positioned in the middle, the expression pattern of self-limited acute ITP has greater similarity to that of healthy controls.