Figure 1.

Hierarchical clustering identifies 8 cluster groups in high-risk ALL. Hierarchical clustering using 254 genes (provided in supplemental Table 7A) was used to identify clusters of patients with shared patterns of gene expression. Rows indicate 207 high-risk ALL patients from COG P9906; and columns, 254 probe sets. Shades of red represent expression levels higher than the median; and green, levels lower than the median. The cluster groups are numbered and prefixed by their method of probe set selection: H indicates high CV; C, COPA; and R, ROSE. (A) HC method for selection of probe sets. (B) COPA selection of probe sets. (C) ROSE selection of probe sets.