Gene co-expression modules in human whole blood. Detection of gene co-expression modules in human whole blood datasets comprised of ALS patients and matched controls. (a) Branches of the cluster dendrogram of the most connected genes gave rise to five gene coexpression modules (Blue, Green, Red, Turquoise and Yellow). Genes that could not be clustered into one of these modules were assigned to the Grey module. Every gene represents a line in the hierarchical cluster. Distance between two genes is shown as height on the y-axis. (b) Boxplots showing gene significance per module. Module significance was calculated by taking the average of the absolute t statistics of all genes within a module. The Blue and Yellow module were the only modules that were significant at a Bonferroni corrected significance threshold of 0.05/5 in all 3 datasets.