Figure 1.

A network graph based on transcripts correlating with the hippocampal pyramidal- and granule cell layer volume traits (green nodes). Interactions have been filtered for an absolute correlation above 0.57 and are colored following the key shown. The graphing algorithm has attempted to draw stronger interactions as shorter lines, with the result that transcripts with similar expression patterns tend to cluster together. Two main clusters can be discerned; one, very dense, at the bottom of the image, is clearly associated with the granule cell layer volume trait and, to a lesser extent, the pyramidal cell layer volume trait. A second cluster, to the upper left, is hardly connected to pyramidal cell layer volume at all. Such a representation reveals the relationship between clusters of transcripts linked to the different phenotypes, thus potentially uncovering cell type-specific genetic pathways. Representation in tables alone would obscure such relationships.