Classification and treatment response prediction in schizophrenia
background Schizophrenia is a severe
psychiatric disorder affecting about 1% of the
population which is characterised by delusions
and hallucinations, in addition to a range of negative
symptoms. The heritability of the disease is
estimated around 80%. However, little is known
about the influence of genetics and transcriptomics
on treatment response.
aim Therefore, in the present study, we
aim to identify genes and gene networks that can
be used for classification and treatment response,
using gene expression.
methods We are using whole-genome
gene expression profiling for the study of the
molecular basis of schizophrenia using whole
blood and brain tissue of schizophrenia patients.
Patients include medicated as well as unmedicated
individuals in addition to unaffected controls.
In addition to case-control comparisons
using a fdr correction, this data was analyzed
using a weighted gene co-expression method.
Clustering was performed to create networks of
co-expressed genes. This in turn resulted in reconstruction
of a limited number of groups of genes
('modules') with highly similar expression profiles.
Within the co-expression modules, the most
connected genes are driving that group of genes
and are considered to be most important.
results Differences in network structure
and connectivity between cases and controls
were found and will point to genes of interest in
the aetiology of schizophrenia. In addition, the
effects of medication on gene-expression are
assessed.
conclusion These effects can give
insight into treatment-response and will be of
importance in further studies in which medication-
naive material is unavailable. Since for most
subjects, genome-wide snp and dna methylation
data is has been collected, we expect that analysis
of multiple layers of genomic simultaneously
will provide new insights into the aetiology of the
disease.