Fig. 2.

Hierarchical cluster analysis of the expression levels of 593 genes differentially expressed at PID 0, PID 2, and PID 4. Clustering was done with the BRB-Array Tools by sample and by gene with the Complete Linkage Algorithm. Genes are represented horizontally, and the individual sacral spinal cord samples are represented vertically. Colors indicate expression level. Genes expressed above average are represented in red; genes expressed below average are shown in green. The degree of red or green intensity indicates the degree of up- or downregulation relative to the average level of expression across all samples.