Variance of Gene Expression Identifies Altered Network Constraints in Neurological Disease
Figure 4
Expression variance discriminates between disease groups.
A. Box plots showing whole-genome phenotype-specific mean expression levels and the corresponding CVs for hONS cells derived from the Control, PD, and SZ patient groups. As can be seen, there is no difference in the average log2(expression) measures but noticeable differences in the CVs. Using a two-sample t-test, there is a significant difference between the SZ and Control groups (p-value<2.2×10−16) and the PD and Control groups (p-value<0.0013). B. The observation of increase in high-variance genes for PD and increase in low-variance genes for SZ persists with different percentile cutoffs applied to the variance distribution in the MAPK signaling pathway. C. Ratios of gene counts for the attract pathways, showing a trend towards high-variance genes for PD and a significant increase in low-variance genes for SZ.