GSE184234
Intellectual disability associated with craniofacial dysmorphism due to POLR3B mutation and defect in spliceosomal machinery
Intellectual disability (ID) is a clinically important disease and a most prevalent neurodevelopmental disorder. The etiology and pathogenesis of ID are poorly recognized.   Exome sequencing revealed a homozygous missense mutation in the POLR3B gene in a consanguineous family with three Intellectual disability with craniofacal anomalies patients. POLR3B gene encoding the second largest subunit of RNA polymerase III. To explore how genetic variants alter cell expression in ID patients, RNA sequencing on blood samples was performed and to obtain insights into the biological pathways influenced by POLR3B mutation, we applied our RNA-Seq data to several gene ontology programs such as ToppGene, Enrichr, KEGG. We detected a significant decrease expression of several spliceosomal RNAs, ribosomal proteins and transcription factors in our ID patients. We hypothesize that POLR3B mutation dysregulates the expression of some important transcription factors, ribosomal and spliceosomal genes and impairments in protein synthesis and splicing mediated in part by transcription factors such as FOXC2, GATA1, .. contribute to impaired neuronal function and concurrence of intellectual disability and craniofacial anomalies in our patients. Our study highlights the emerging role of spliceosome and ribosomal proteins in intellectual disability. Overall design: comparison of expression profile between intellectual disability patients and controls