Coordinated expression of genes is critical to brain development and function. One expectation of polygenic inheritance of disease is that this coordination may be subtly altered in individuals with SCZ. To assess this, we applied weighted gene co-expression network analysis (WGCNA) to the matrix of pairwise gene co-expression values. WGCNA recovers a network that consists of nodes (genes) and edges connecting nodes (i.e., the degree of co-expression for a pair of genes, measured as their correlation after transformation by raising the value to a power β that results in an overall scale-free topology). WGCNA divides the network into subnetworks called modules, or clusters of genes with more highly correlated expression.
