Limited Association between Schizophrenia Genetic Risk Factors and Transcriptomic Features

Area of Science:

• Neurogenetics
• Psychiatric Disorders
• Genomics and Transcriptomics

Background:

• Schizophrenia is a complex polygenic disorder influenced by numerous genetic risk factors.
• Most schizophrenia-associated genetic variants are in non-coding regions, impacting gene regulation.
• Transcriptomic dysregulation is observed in schizophrenia, but its link to genetic risk is unclear.

Purpose of the Study:

• To investigate if gene expression features contribute to schizophrenia heritability.
• To explore the relationship between genetic risk factors and transcriptomic profiles in schizophrenia.

Main Methods:

• Utilized quantitative trait loci and chromatin interaction data to link schizophrenia risk variants to genes.
• Assigned risk variants to genes representing differentially expressed genes (DEGs), co-expression networks, and gene hubness.
• Employed stratified linkage disequilibrium score regression to estimate heritability enrichment for these gene expression features.

Main Results:

• Differentially expressed genes (DEGs) and co-expression networks showed nominal enrichment for schizophrenia heritability.
• Cellular heterogeneity partially explained this association, with DEGs showing cell type-specific links to genetic risk.
• DEGs were enriched for target genes of schizophrenia-associated transcription factors, indicating regulatory cascade involvement.

Conclusions:

• Schizophrenia's genetic risk factors are associated with specific transcriptomic features, including DEGs and co-expression networks.
• Transcriptomic signatures in schizophrenia likely arise from transcriptional regulatory cascades initiated by genetic risk.
• Understanding these links is crucial for deciphering the genetic architecture of schizophrenia.