Analysis of differentially expressed genes in bipolar disorder: transcriptomic signature of adolescence and young adulthood in working memory-relared area

Bipolar disorder (BD) is a heritable severe illness. One of the indications of BD is working memory (WM) impairment which is a heritable cognitive trait. The aim of the current study is to identify the transcriptomic level developmental biomarkers of BD in WM-related brain regions. We based our analysis on adolescence and young adulthood (AYA), the critical period for both BD and cognitive development. We have chosen 4 publicly available microarray datasets from Gene Omnibus database for which one is derived from healthy controls and three from bipolar disorder patients. We compared different developmental periods of the brains of normal subjects to determine healthy brain development at the transcriptomic level. After applying the same method to detect bipolar development to show differences between BD and healthy brains. We followed these comparisons in two steps; on gene-level analysis and geneset level analysis. Next, we identified common genes and pathways from the results of different analyses. As a result of this comparison, while six genes were identified differentially expressed, we observed 5 Gene Ontology (GO) genesets shown different regulation patterns in bipolar and healthy brains. The literature review has been shown that the significant biological pathways might be influenced by the treatment.