Exon- and gene-Level transcriptional profiling in Lymphoblastoid Cell Lines (LCLs) from Williams syndrome patients and controls

Williams syndrome (WS), characterized by positive sociality, provides a unique model for studying transcriptional networks underlying social dysfunction, relevant to disorders like autism spectrum disorder (ASD) and schizophrenia (SCHZ). In a cohort lymphoblastoid cell lines derived from 52 individuals (34 WS patients, 18 parental controls), genome-wide exon-level arrays identified a core set of differentially expressed genes (DEGs), with WS-deleted genes ranking among the top transcripts. Findings were validated by PCR, RNA-seq, and western blots. Network analyses revealed perturbed actin cytoskeletal signaling in excitatory dendritic spines, alongside interactions in MAPK, IGF1-PI3K-AKT-mTOR/insulin, and synaptic actin pathways. These transcriptional networks show parallels to ASD and SCHZ, highlighting shared mechanisms across social behavior disorders. Human lymphoblastoid cells immortailzed from WIlliams syndrome patients and non-affected parental controls were grown in RMPI 1640 with 10% FBS, 5% pen/strep, 5% L-glutamine and 0.5% gentamycin. Total RNA was extracted from each culture using the Qiagen RNeasy kit with DNase digestion. Prior to labeling, ribosomal RNA was removed from total RNA (1 μg per sample) using the RiboMinus Human/Mouse Transcriptome Isolation Kit (Invitrogen). Expression analysis was conducted using Affymetrix Human Exon 1.0 ST arrays following the Affymetrix hybridization protocols. Exon expression data were analyzed through Affymetrix Expression Console using exon- and gene-level PLIER (Affymetrix Power Tool with PM-GCBG background correction) summarization and sketch-quantile normalization methods.