Simultaneous Analysis of
Expression Levels of Many Genes in Post-Mortem Brain Tissue from Individuals with Schizophrenia
and Bipolar Disease
K. Faridi*, K. Hyder, A.
Chenchik, N.L. Johnston, R.H.Yolken, and the Stanley
Neuropathology Consortium. The Stanley Division of Developmental
Neurovirology
Johns Hopkins University School of Medicine, 600 N. Wolfe
St./Blalock 1111
Baltimore, MD 21287-4933, USA
The analysis of expression levels of genes
in the post-mortem brains of individuals with schizophrenia and
bipolar disease is a potentially important method in
understanding the molecular basis of these diseases. The
simultaneous analysis of levels of a large number of genes is
particularly valuable, allowing the evaluation of functionally
related gene groups.
We used the Clontech Atlas Human I cDNA
Expression Array to simultaneously analyze levels of 588 genes.
Total RNA was extracted from cerebellar brain tissue. This RNA
was used to generate 32P-labelled cDNA probes, which
were hybridized to the membrane array. Autoradiograph images of
each array were then analyzed using ImageQuaNT software
(Molecular Dynamics) generating a value for each gene. A total of
22 samples were analyzed, including four brains from
schizophrenics, six from bipolar individuals, five from
clinically depressed individuals, and seven normal controls.
ANOVA analysis was performed to compare the levels of each gene
between the four disease groups. Several genes were found to be
significantly differentially expressed in patients and controls.
In addition, for each disease, total RNA from four samples was
pooled, and this mixture was hybridized to the array. The largest
differences were seen in levels of glutathione S-transferase
microsomal (raised in schizophrenic and bipolar) and glutathione
S-transferase theta-1 (depressed in schizophrenic).