RNA sequencing and quality control (QC) steps are described in detail in Supplement 1. In brief, messenger RNA (mRNA) sequencing was performed at a targeted depth of 40 million reads per sample using the Illumina NextSeq 500 platform (Illumina Inc, San Diego, CA). mRNA reads (4 regions, 16 subjects) were mapped to 58,243 transcripts (Fig. S1), which were further reduced to 18,993 expressed RefSeq genes (v.2015-01). Of those, genes were retained that had at least 1 count per million in at least half of the samples for at least one brain region and if over all subjects and brain regions, gene j’s coefficient of variation CVj < T, where T is defined as the mean of CVj over all j plus 3 standard deviations of CV. This resulted in 14,211 genes whose expression passed QC. Next, we evaluated pairwise consensus correlations over genes. Correlation was high between BA11 and BA47, 0.71, compared to others (0.16–0.25; Fig. S2). Thus, data for BA11 and BA47 were treated as a single brain region termed “OFC” by averaging expression, per gene and subject, over
