RESUMEN
Objective:To identify Down syndrome (DS) fetal encephalopathy related genes and signaling pathways via bioinformatics analysis, and to explore their potential mechanisms underlying the occurrence and development of DS neuropathology.Methods:Retrospective study.In December 2021, dataset GSE59630 was downloaded from the gene expression omnibus (GEO), and differentially expressed genes (DEGs) between DS and normal fetal brain tissue were identified by R software.Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and gene set enrichment analysis (GSEA) were performed on the genes identified.The protein-protein interaction (PPI) network was constructed based on search tool for the retrieval of interacting genes online database and Cytoscape software, and key modules and hub DEGs were identified.Real-time quantitative polymerase chain reaction technique was used to verify the expression of hub genes related to neurodegeneration in brain tissue of 3 pairs of DS and normal fetuses at the gestational age of 22-33 weeks.Results:A total of 225 DEGs were screened out from DS and normal fetal brain tissue, including 18 up-regulated genes and 207 down-regulated genes.GO functional enrichment analysis showed that DEGs were mainly enriched in neurogenesis, neuronal apoptosis, transcriptional regulation, mitochondrial energy metabolism, etc.KEGG pathway enrichment analysis revealed that DEGs were associated with a variety of neurodegenerative diseases.GSEA suggested that apoptosis and inflammatory responses play a vital part in the occurrence of DS neuropathology.Ten hub genes were identified by the PPI network established, and they were mainly related to histone acetylation and transcriptional regulation.According to the tissue verification result, the variations of RAB8A, TBP and TAF6 expression conformed to the microarray data. Conclusions:The key genes and signaling pathways identified by transcriptome analysis of fetal brain tissue facilitate the comprehensive understanding of the molecular mechanism of DS neuropathology.This study provides a novel insight into the clinical diagnosis and treatment of neurodevelopmental abnormalities and mental retardation in DS.