Total RNA from postmortem human prefrontal cortex was extracted from frozen tissue, excluding any samples with contaminated or degraded quality (RNA integrity numbers less than 5.0). Ribosomal RNA was depleted using RiboMinus Eukaryote kit for RNA-Seq and confirmed using an Agilent Bioanalyzer. Samples were processed using ABI whole transcriptome library preparation kit and sequenced on the ABI SOLiD 4 system using paired-end reads (35+50 bp). Collected reads were processed by the Texas Advanced Computing Center and mapped for sequence reads, allowing two mismatches per 25 bp seed length, against the human reference genome (hg19), to select unique alignments with the highest reproducible mapping. Read counts were generated using the Partek Genomics Suite software (a minimum of five reads/alignment was used to determine values). Abundance was calculated for full-length gene isoforms with an expectation-maximization algorithm 20. Detection of differential expression based on the negative binomial distribution for modeled read counts, and normalization using a regularized log2 transformation 21, was conducted within the R project for statistical computing. Expression data encompassed all sequencing reads that were unambiguously mapped to a single gene within an individual sample.
