Hierarchical clustering analysis.

(A) Gene expression values were log transformed (log base 2) and median centered across each sample. Analysis was performed with Cluster and TreeView software. Each row represents a separate gene and each column a separate mRNA sample. The dendrogram at the left shows the relationship of the genes according to the similarity of their expression profile across samples and the dendrogram at the top depicts the relationship of the samples according to the similarity in their gene expression profile. Each value represents the difference from the gene median and is depicted according to the color scale shown at the bottom (−3 to +3 on a log base 2 scale). Vertical bars on the right indicate clusters of coordinately expressed genes in either myeloma samples or LCLs. (B) Enlargement of the MM cluster. Black arrows point out genes overexpressed in MM samples that were previously described in MM. Red arrows point out genes overexpressed in MM samples that were not previously linked to MM. (C) Enlargement of the LCL cluster. Black arrows point out genes overexpressed in LCL samples that were previously described in LCL. See our Web site for full data (http://www.u475.montp.inserm.fr/).