Transcription profiling of human trisomy 21 fibroblasts
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ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Elizabeth Salomon
PROVIDER: E-GEOD-9762 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Down syndrome (DS) is caused by an extra copy of chromosome 21. We are characterizing protein changes in human skin fibroblasts. We propose to study corresponding changes at the DNA level (by SNP analysis) and the RNA level (using Affymetrix chips). These studies will detail transcriptional and translational regulation in trisomy. The Specific Aim is to obtain data on RNA transcript levels using Affymetrix expression arrays in a group of trisomy 21 and euploid fibroblast cell lines. In parallel, we will acquire SNP data to determine both genotype (call) and copy number changes for trisomic samples. The results will allow us to identify the patterns of change in a trisomic chromosome (relative to control). [1] We hypothesize that in genomic DNA samples derived from trisomy 21 (TS21) fibroblasts there will be an increased copy number on chr21 with additional microdeletions and microdeletions. [2] We hypothesize that the RNA transcripts derived from chr21 will be elevated relative to euploid controls. [3] We hypothesize that altered RNA transcript levels will be significantly correlated with altered protein levels from these same fibroblast cell lines. The experimental design is as follows. All samples are from deidentified individuals and were obtained from the Brain and Tissue Bank for Developmental Disorders at the University of Maryland, with Johns Hopkins IRB approval.[1] There are five trisomy 21 samples and five euploid samples (total n=10). Fibroblasts were grown in culture to comparable confluency and passage number. Cells were harvested. Total RNA was isolated with a Qiagen kit. The quantity and purity of the RNA was confirmed by spectrophotometry and by electrophoresing an aliquot on a 1% agarose gel. Approximately 10 micrograms of total RNA will be sent to TGen on dry ice for analysis on Affymetrix U133 PlusTwo arrays. Data analysis will be with Affymetrix and Partek software. Keywords: other
2007-12-04 | GSE9762 | GEO
Project description:Down syndrome is a common disorder with enormous medical and social costs, caused by trisomy for Chr21. We tested the concept that gene imbalance across an extra chromosome can be de facto corrected in DS patient stem cells by manipulating a single gene, XIST. Using zinc finger nucleases, we targeted a large, inducible XIST transgene into the Chr21 DYRK1A locus, in DS pluripotent stem cells. XIST RNA coats Chr21 and triggers stable heterochromatin modifications, chromosome-wide transcriptional silencing and DNA methylation to form a “Chr21 Barr Body.” This provides a model to study human chromosome inactivation and creates a system to investigate genomic expression changes and cellular pathologies of trisomy 21, free from genetic and epigenetic noise. In this study, we used microarrays to understand the genome-wide impacts of inducible XIST expression on Chr21 in trisomy 21 human iPS cell lines, and to evaluate the extent of Chr21 silencing trisomic samples versus a disomic male iPS cell line.
2013-07-12 | GSE47014 | GEO
Project description:To understand the molecular basis of Down syndrome pathogenesis, we performed a transcriptome analysis of nine different tissues in Ts65Dn, an established mouse model of human trisomy 21. Ts65Dn mice have segmental trisomy of mouse chromosome 16 with ca. 128 genes at dosage imbalance (Reeves et al. 1995). The Ts65Dn mouse is widely used as a model for studies of DS because it is at dosage imbalance for the orthologs of about half the 284 Chr21 genes. Ts65Dn mice have several features that directly parallel developmental anomalies of DS. We compare here the expression of 136 mouse orthologs of Chr21 genes, 77 of which are triplicated in Ts65Dn, in trisomic and euploid mice. <br> <br> We designed a mouse cDNA expression array interrogating 136 mmu21 genes. RNA pools from four adult male Ts65Dn mice and four male euploid littermates were prepared from cortex and dissected from three to four month-old mice. Directly labeled first strand cDNA probes from nine different tissues were hybridized to the arrays in replicated hybridizations. A total of 446 genes that are not triplicated in Ts65Dn mice served as controls. These included 62 mmu21 genes from MMU10, MMU17, and non-triplicated portions of MMU16, plus 384 randomly distributed mouse cDNAs from the Unigene collection.
2004-04-23 | E-MEXP-102 | biostudies-arrayexpress
Project description:Congenital development disorders with variable severity occur in trisomy 21. However, how these phenotypic abnormalities develop with variations remains elusive. We hypothesize that the difference in euploidy gene expression variation among trisomy 21 tissues are perturbed by the presence of an extra copy of chromosome 21 and this may contribute to the phenotypic variations in Down syndrome. Experiment Overall Design: We used DNA microarray to measure the differences in gene expression variance (representing variation) between four human trisomy 21 amniocytes and six human euploid amniocytes.
2008-04-03 | E-GEOD-10758 | biostudies-arrayexpress
Project description:Down syndrome is a common disorder with enormous medical and social costs, caused by trisomy for Chr21. We tested the concept that gene imbalance across an extra chromosome can be de facto corrected in DS patient stem cells by manipulating a single gene, XIST. Using zinc finger nucleases, we targeted a large, inducible XIST transgene into the Chr21 DYRK1A locus, in DS pluripotent stem cells. XIST RNA coats Chr21 and triggers stable heterochromatin modifications, chromosome-wide transcriptional silencing and DNA methylation to form a M-bM-^@M-^\Chr21 Barr Body.M-bM-^@M-^] This provides a model to study human chromosome inactivation and creates a system to investigate genomic expression changes and cellular pathologies of trisomy 21, free from genetic and epigenetic noise. In this study, we used microarrays to understand the genome-wide impacts of inducible XIST expression on Chr21 in trisomy 21 human iPS cell lines, and to evaluate the extent of Chr21 silencing trisomic samples versus a disomic male iPS cell line. Three independently targeted subclones plus the parental Chr21 trisomic (non-targeted) iPS cell line were grown M-BM-1 doxycycline (2 M-BM-5g/ml) for 22 d. Normal male iPS line was also cultured for 22 d and total RNA was extracted with a High Pure RNA extraction kit (Roche) in triplicate for each, processed with a Gene Chip 3M-bM-^@M-^Y IVT Express Kit (Affymetrix), and hybridized to Affymetrix human gene expression PrimeView arrays. Array normalization was performed with Affymetrix Expression Console Software with Robust Multichip Analysis (RMA). Probesets with the top 60% of signal values were considered present and M-bM-^@M-^\expressedM-bM-^@M-^] and were used for all further analysis. In total 9 RNA samples were prepared in triplicate for a total of 27 arrays.
2013-07-12 | E-GEOD-47014 | biostudies-arrayexpress
Project description:Trisomy 21 (T21) is the most frequent genetic cause of cognitive impairment. To assess the perturbations of gene expression in T21, and to eliminate the noise of the genomic variability, we studied the transcriptome of fetal fibroblasts from a pair of monozygotic twins discordant for T21. Here we show that the differential expression between the twins is organized in domains along all chromosomes that are either up- or downregulated. These gene expression dysregulation domains (GEDDs) can be defined by the expression level of their gene content, and are well conserved in induced pluripotent stem cells derived from the twinsM-bM-^@M-^Y fibroblasts. Comparison of the transcriptome of the Ts65Dn mouse model of DS and wild-type, also showed GEDDs along the mouse chromosomes that were syntenic in human. The GEDDs correlate with the lamina-associated (LADs) and replication domains of mammalian cells. The overall LADs position was not altered in trisomic cells. However, the H3K4me3 profile of the trisomic fibroblasts was modified and accurately followed the GEDD pattern. These results suggest that the nuclear compartments of trisomic cells undergo modifications of the chromatin environment influencing the overall transcriptome and that GEDDs may therefore contribute to some T21 phenotypes. mRNA-Seq profiling in Down syndrome: fibroblasts derived from a pair of monozygotic twins discordant for trisomy 21 (4 replicates), iPS cells from the same pair of discordant twins, fibroblasts from a pair of normal monozygotic twins, fibroblasts from 16 unrelated individuals (8 trisomic and 8 euploid controls), fibroblasts from the Ts65Dn mouse model of Down syndrome (1 trisomic mouse and 1 control wt).
2014-04-08 | E-GEOD-55504 | biostudies-arrayexpress
Project description:This study examines cortical organoids generated from a panel of isogenic trisomic and disomic iPSC lines (subclones) as a model of early fetal brain development in Down syndrome. An initial experiment comparing organoids from one trisomic and one disomic line showed many genome-wide transcriptomic differences and modest differences in cell-type proportions, suggesting there may be a neurodevelopmental phenotype that is due to trisomy of chr 21. To better control for multiple sources of variation, we undertook a highly robust study of ∼1,200 organoids using an expanded panel of six all-isogenic lines, three disomic, and three trisomic. The power of this experimental design was indicated by strong detection of the ∼1.5- fold difference in chr21 genes. However, the numerous expression differences in non-chr21 genes seen in the smaller experiment fell away, and the differences in cell-type representation between lines did not correlate with trisomy 21. Results suggest that the initial smaller experiment picked up differences between small organoid samples and individual isogenic lines, which “averaged out” in the larger panel of isogenic lines. Our results indicate that even when organoid and batch variability are better controlled for, variation between isogenic cell lines (even subclones) may obscure, or be conflated with, subtle neurodevelopmental phenotypes that may be present in ∼2nd trimester DS brain development. Interestingly, despite this variability between organoid batches and lines, and the “fetal stage” of these organoids, an increase in secreted Aβ40 peptide levels—an Alzheimer-related cellular phenotype—was more strongly associated with trisomy 21 status than were neurodevelopmental shifts in cell-type composition.
2023-01-07 | GSE222365 | GEO
Project description:Down syndrome, caused by trisomy 21, is a complex developmental disorder associated with intellectual disability and reduced growth of multiple organs. Structural pathologies are present at birth, reflecting embryonic origins. A fundamental unanswered question is how an extra copy of human chromosome 21 contributes to organ-specific pathologies that characterize individuals with Down syndrome. Relevant to the hallmark intellectual disability in Down syndrome, how does trisomy 21 affect neural development? We tested the hypothesis that trisomy 21 exerts effects on human neural development as early as neural induction. Bulk RNA sequencing was performed on isogenic trisomy 21 and euploid human induced pluripotent stem cells (iPSCs) at successive stages of neural induction: embryoid bodies at Day 6, early neuroectoderm at Day 10, and differentiated neuroectoderm at Day 17. Gene expression analysis revealed over 1,300 differentially expressed genes in trisomy 21 cells along the differentiation pathway compared to euploid controls. Less than 5% of the gene expression changes included upregulated chromosome 21 encoded genes at every timepoint. Genes involved in specific growth factor signaling pathways (Wnt and Notch), metabolism (including interferon response and oxidative stress), and extracellular matrix were altered in trisomy 21 cells. Further analysis revealed heterochronic expression of genes. This comprehensive analysis reveals that trisomy 21 impacts discrete developmental pathways at the earliest stages of neural development. Further, the results suggest that metabolic dysfunction arises early in embryogenesis in trisomy 21 and may thus affect development and function more broadly.
2024-01-31 | GSE247990 | GEO
Project description:Background: Among full autosomal trisomies, only trisomies of chromosome 21 (Down syndrome, DS), 18 (Edward syndrome, ES) and 13 (Patau syndrome, PS) are compatible with postnatal survival. But the mechanisms, how a supernumerary chromosome disrupts the normal development and causes specific phenotypes, are still not fully explained. As an alternative to gene dosage effects due to the trisomic chromosome, a genome-wide transcriptional dysregulation has been postulated. The aim of this study was to define the transcriptional changes in trisomy 13, 18, and 21 during early fetal development in order to define whether (1) overexpression of genes of the trisomic chromosome contributes solely to the phenotype, if (2) all genes of the trisomic chromosome are upregulated similarly and whether the ratio of gene expression is in agreement with the gene dosis, (3) whether the different trisomies behave similarly in the characteristics of transcriptional dysregulation, and (4) whether transcriptional pattern can be potentially used in prenatal diagnosis. Methods: Using oligonucleotide microarrays (Affymetrix, U133 Plus 2.0), we analyzed whole genome expression profiles representing 54.000 probe sets in cultured amniocytes (AC) and chorion villus cells (CV) from pregnancies with a normal karyotype and with trisomies of human chromosomes 21, 18 and 13. Findings: We observed a low to moderate up-regulation for a subset of genes of the trisomic chromosomes. Transcriptional level of approximately 12-13 % of the supernumerary chromosome appeared similar to the respective chromosome pair in normal karyotypes. Expression values as well as the expression patterns of genes from the trisomic chromosome can distinguish the respective trisomic samples from euploid controls. A subset of chromosome 21-genes including the DSCR1-gene involved in fetal heart development was consistently up-regulated in different tissues (AC, CV) of trisomy 21 fetuses whereas only minor changes were found for genes of all other chromosomes. In contrast, in trisomy 13 and trisomy 18 vigorous downstream transcriptional changes were found. Interpretation: Global transcriptome analysis for autosomal trisomies 13, 18, and 21 supported a combination of the two major hypotheses. As several transcriptional pathways are altered, complex regulatory mechanisms are involved in the pathogenesis of autosomal trisomies. A genome-wide transcriptional dysregulation was predominantly observed in trisomies 13 and 18, whereas a more to chromosome 21 restricted expression alteration was found in trisomy 21. Experiment Overall Design: The study included the following samples: Three samples with normal chromosomes in Amniocytes (AC) and chorion villus cells (CV) each, three samples with trisomy 13 in AC, three samples with trisomy 18 in CV, and three samples with trisomy 21 in AC and CV each.
2008-06-14 | E-GEOD-6283 | biostudies-arrayexpress
Project description:Background: Among full autosomal trisomies, only trisomies of chromosome 21 (Down syndrome, DS), 18 (Edward syndrome, ES) and 13 (Patau syndrome, PS) are compatible with postnatal survival. But the mechanisms, how a supernumerary chromosome disrupts the normal development and causes specific phenotypes, are still not fully explained. As an alternative to gene dosage effects due to the trisomic chromosome, a genome-wide transcriptional dysregulation has been postulated. The aim of this study was to define the transcriptional changes in trisomy 13, 18, and 21 during early fetal development in order to define whether (1) overexpression of genes of the trisomic chromosome contributes solely to the phenotype, if (2) all genes of the trisomic chromosome are upregulated similarly and whether the ratio of gene expression is in agreement with the gene dosis, (3) whether the different trisomies behave similarly in the characteristics of transcriptional dysregulation, and (4) whether transcriptional pattern can be potentially used in prenatal diagnosis. Methods: Using oligonucleotide microarrays (Affymetrix, U133 Plus 2.0), we analyzed whole genome expression profiles representing 54.000 probe sets in cultured amniocytes (AC) and chorion villus cells (CV) from pregnancies with a normal karyotype and with trisomies of human chromosomes 21, 18 and 13. Findings: We observed a low to moderate up-regulation for a subset of genes of the trisomic chromosomes. Transcriptional level of approximately 12-13 % of the supernumerary chromosome appeared similar to the respective chromosome pair in normal karyotypes. Expression values as well as the expression patterns of genes from the trisomic chromosome can distinguish the respective trisomic samples from euploid controls. A subset of chromosome 21-genes including the DSCR1-gene involved in fetal heart development was consistently up-regulated in different tissues (AC, CV) of trisomy 21 fetuses whereas only minor changes were found for genes of all other chromosomes. In contrast, in trisomy 13 and trisomy 18 vigorous downstream transcriptional changes were found. Interpretation: Global transcriptome analysis for autosomal trisomies 13, 18, and 21 supported a combination of the two major hypotheses. As several transcriptional pathways are altered, complex regulatory mechanisms are involved in the pathogenesis of autosomal trisomies. A genome-wide transcriptional dysregulation was predominantly observed in trisomies 13 and 18, whereas a more to chromosome 21 restricted expression alteration was found in trisomy 21. Keywords: Trisomy, Down syndrome, Patau syndrome, Edward syndrome, microarray, gene expression, amniocytes, chorion villus cells, gene dosage effect, DSCR1
2006-12-01 | GSE6283 | GEO