Homo sapiens
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PROVIDER: PRJNA272805 | ENA |
REPOSITORIES: ENA
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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
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:We profiled gene expression at the maternal-fetal interface during the second trimester of pregnancy (13-22 wks) in trisomy 13 (T13; Patau syndrome, n = 4), trisomy 18 (T18; Edwards syndrome, n = 4), trisomy 21 (T21; Down syndrome, n = 8), and in euploid pregnancies (n = 4). FISH confirmed the ploidy of the samples. Global transcriptional profiling identified differentially expressed transcripts (? 2-fold) in T21 (n = 160), T18 (n = 80), and T13 (n = 125). The majority were upregulated. Unexpectedly, most of the misexpressed genes were not located on the relevant trisomic chromosome, suggesting genome-wide dysregulation. A much smaller proportion of the differentially expressed transcripts were encoded on the aneuploid chromosome, also implicating gene dosage (1-5). In T21, <10% of the genes were transcribed from that chromosome, all but one from the Down syndrome critical region (21q21-22), which is postulated to play an important role in the clinical phenotype. For T13 and T18, a higher proportion of the overexpressed genes were located on the trisomic chromosome. In T13, 15% of the upregulated genes were on the affected chromosome; 15 resided on the long arm, 13q11-14. In T18, the percentage increased to 24, 15 of which were also located on the long arm (18q11-22). Our data suggested that the placental (and possibly fetal) phenotypes that are associated with T13, T18 and T21 are driven by the combined effects of genome-wide phenomena and increased gene dosage from critical regions of the triploid chromosome. We profiled gene expression at the maternal-fetal interface during the second trimester of pregnancy (13-22 wks) in trisomy 13 (T13; Patau syndrome, n = 4), trisomy 18 (T18; Edwards syndrome, n = 4), trisomy 21 (T21; Down syndrome, n = 8), and in euploid pregnancies (n = 4). FISH confirmed the ploidy of the samples.
2015-06-23 | E-GEOD-70102 | biostudies-arrayexpress
Project description:Genome wide DNA methylation profiling of normal and trisomic placentas, and maternal blood cell DNA. The aim of this study was to search for methylation differences between maternal and fetal(placenta) cell free DNA, and between normal and trisomic placentas for an optimized methylation based noninvasive prenatal diagnosis of fetal chromosomal aberations. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in DNA samples from Chorionic villus samples(CVS) and DNA samples from whole blood. Samples included 12 Maternal blood cell samples from normal pregnancies, 12 normal CVS, 12 Trisomy 21 CVS, 12 trisomy 18 CVS and 6 trisomy 13 CVS samples.
2015-03-31 | GSE66210 | GEO
Project description:Gene expression of mandibular precursor from embryonic day 13.5 trisomic and euploid embryos from the Ts65Dn Down syndrome mouse model. Results provide insight into importance of non-trisomic genes in organogenesis. Total RNA isolated from mandibular precursor of 13 trisomic and 11 euploid E13.5 embryos.
2010-11-02 | E-GEOD-24554 | biostudies-arrayexpress
Project description:We profiled gene expression at the maternal-fetal interface during the second trimester of pregnancy (13-22 wks) in trisomy 13 (T13; Patau syndrome, n = 4), trisomy 18 (T18; Edwards syndrome, n = 4), trisomy 21 (T21; Down syndrome, n = 8), and in euploid pregnancies (n = 4). FISH confirmed the ploidy of the samples. Global transcriptional profiling identified differentially expressed transcripts (≥ 2-fold) in T21 (n = 160), T18 (n = 80), and T13 (n = 125). The majority were upregulated. Unexpectedly, most of the misexpressed genes were not located on the relevant trisomic chromosome, suggesting genome-wide dysregulation. A much smaller proportion of the differentially expressed transcripts were encoded on the aneuploid chromosome, also implicating gene dosage (1-5). In T21, <10% of the genes were transcribed from that chromosome, all but one from the Down syndrome critical region (21q21-22), which is postulated to play an important role in the clinical phenotype. For T13 and T18, a higher proportion of the overexpressed genes were located on the trisomic chromosome. In T13, 15% of the upregulated genes were on the affected chromosome; 15 resided on the long arm, 13q11-14. In T18, the percentage increased to 24, 15 of which were also located on the long arm (18q11-22). Our data suggested that the placental (and possibly fetal) phenotypes that are associated with T13, T18 and T21 are driven by the combined effects of genome-wide phenomena and increased gene dosage from critical regions of the triploid chromosome.
2015-06-23 | GSE70102 | GEO
Project description:Genome wide DNA methylation profiling of normal and trisomic placentas, and maternal blood cell DNA. The aim of this study was to search for methylation differences between maternal and fetal(placenta) cell free DNA, and between normal and trisomic placentas for an optimized methylation based noninvasive prenatal diagnosis of fetal chromosomal aberations. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in DNA samples from Chorionic villus samples(CVS) and DNA samples from whole blood. Samples included 12 Maternal blood cell samples from normal pregnancies, 12 normal CVS, 12 Trisomy 21 CVS, 12 trisomy 18 CVS and 6 trisomy 13 CVS samples. Bisulphite converted DNA from the 54 samples were hybridized to the Illumina Infinium 450k Human Methylation Beadchip.
2015-03-31 | E-GEOD-66210 | 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: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.
2008-06-16 | E-GEOD-9762 | biostudies-arrayexpress
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