| 1 | Psychiatr. Genet. 2008 Dec 18: 295-301 |
|---|---|
| PMID | 19018235 |
| Title | Polymorphisms of coding trinucleotide repeats of homeogenes in neurodevelopmental psychiatric disorders. |
| Abstract | Autism (MIM#209850) and schizophrenia (MIM#181500) are both neurodevelopmental psychiatric disorders characterized by a highly genetic component. Homeogenes and forkhead genes encode transcription factors, which have been involved in brain development and cell differentiation. Thus, they are relevant candidate genes for psychiatric disorders. Genetic studies have reported an association between autism and DLX2, HOXA1, EN2, ARX, and FOXP2 genes whereas only three studies of EN2, OTX2, and FOXP2 were performed on schizophrenia. Interestingly, most of these candidate genes contain trinucleotide repeats coding for polyamino acid stretch in which instability can be the cause of neurodevelopmental disorders. Our goal was to identify variations of coding trinucleotide repeats in schizophrenia, autism, and idiopathic mental retardation. We screened the coding trinucleotide repeats of OTX1, EN1, DLX2, HOXA1, and FOXP2 genes in populations suffering from schizophrenia (247 patients), autism (98 patients), and idiopathic mental retardation (56 patients), and compared them with control populations (112 super controls and 202 healthy controls). Novel deletions and insertions of coding trinucleotide repeats were found in the DLX2, HOXA1, and FOXP2 genes. Most of these variations were detected in controls and no difference in their distribution was observed between patient and control groups. Two different polymorphisms in FOXP2 were, however, found only in autistic patients and the functional consequences of these variations of repeats have to be characterized and correlated to particular clinical features. This study did not identify specific disease risk variants of trinucleotide repeats in OTX1, EN1, DLX2, HOXA1, and FOXP2 candidate genes in neurodevelopmental psychiatric disorders. |
| SCZ Keywords | schizophrenia |
| 2 | PLoS ONE 2013 -1 8: e75682 |
| PMID | 24098394 |
| Title | Transcriptome comparison of human neurons generated using induced pluripotent stem cells derived from dental pulp and skin fibroblasts. |
| Abstract | Induced pluripotent stem cell (iPSC) technology is providing an opportunity to study neuropsychiatric disorders through the capacity to grow patient-specific neurons in vitro. Skin fibroblasts obtained by biopsy have been the most reliable source of cells for reprogramming. However, using other somatic cells obtained by less invasive means would be ideal, especially in children with autism spectrum disorders (ASD) and other neurodevelopmental conditions. In addition to fibroblasts, iPSCs have been developed from cord blood, lymphocytes, hair keratinocytes, and dental pulp from deciduous teeth. Of these, dental pulp would be a good source for neurodevelopmental disorders in children because obtaining material is non-invasive. We investigated its suitability for disease modeling by carrying out gene expression profiling, using RNA-seq, on differentiated neurons derived from iPSCs made from dental pulp extracted from deciduous teeth (T-iPSCs) and fibroblasts (F-iPSCs). This is the first RNA-seq analysis comparing gene expression profiles in neurons derived from iPSCs made from different somatic cells. For the most part, gene expression profiles were quite similar with only 329 genes showing differential expression at a nominally significant p-value (p<0.05), of which 63 remained significant after correcting for genome-wide analysis (FDR <0.05). The most striking difference was the lower level of expression detected for numerous members of the all four HOX gene families in neurons derived from T-iPSCs. In addition, an increased level of expression was seen for several transcription factors expressed in the developing forebrain (FOXP2, OTX1, and LHX2, for example). Overall, pathway analysis revealed that differentially expressed genes that showed higher levels of expression in neurons derived from T-iPSCs were enriched for genes implicated in schizophrenia (SZ). The findings suggest that neurons derived from T-iPSCs are suitable for disease-modeling neuropsychiatric disorder and may have some advantages over those derived from F-iPSCs. |
| SCZ Keywords | schizophrenia |