Reduction in nuclear speckles and transcriptome de-regulation in fibroblast of intellectually disabled patients with mutations at the FRAXE site

Loss of function of FMR2 due to either hypermethylation of the CpG island as a consequence of the expansion of the CCG repeat near its transcription start site, or internal deletion of FMR2 is considered to be the major cause of FRAXE fragile site associated intellectual disability. FMR2 was shown to be a potent transcription activator as well as an RNA binding protein capable of regulating alternative splicing. Using whole transcriptome approach, we aimed to identify genes regulated by FMR2 and to study their contribution to the underlying causes of intellectual disability in the patients. We subjected total RNA extracted from fibroblasts of FRAXE patients (n=8), and unrelated controls (n=4) to Affymetrix Human Exon 1.0 ST array