Figure 1.

Hierarchical clustering showing relative gene expressions comparing patients with MS to their healthy siblings. Genes with at least two-fold up- or down-regulation in 25% of MS twins are presented. Housekeeping genes and ribosomal protein genes are not included. The colorbar on the right shows the color representation of gene expressions. Grey color indicates the lack of expression in cDNA microarray and twin represents twin pair. The column dendrogram on the left shows the similarity between the expression of different genes and column dendrogram above the similarity in the gene expression profiles of twins. The data was visualized with the GeneSpring software version 5.0 (Silicon Genetics, San Carlos, CA, USA) and the detailed principles of the cluster analysis and dendrograms can be found from the GeneSpring GX animated tutorial from the internet http://www.chem.agilent.com/scripts/pds.asp?lpage=27881. See also text for the interpretation of the figure.