Systematic meta-analysis and replication of genome-wide expression studies identifies molecular pathways of Parkinson’s disease

Analysis of human dopamine (DA) from postmortem brains of 8 patients with Parkinson’s disease (PD). Results provide insight into the molecular processes perturbed in the PD substantia nigra. Human dopamine (DA) neurons from 8 PD and 9 control subjects were obtained. Double-stranded complementary DNA was made with a biotinylated T7(dT)-24 primer. Biotinylated complementary RNA was fragmented and hybridized to Affymetrix human genome U133_X3P microarrays. The Affymetrix .CEL files were normalized to “all probe sets” in a standardized matter, and scaled to 100 by the MAS5 algorithm implemented in the Bioconductor package.