Repeat Detector: accurate, efficient, and flexible sizing of expanded CAG/CTG repeats from targeted DNA sequencing
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA817815 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR18364022_subreads.fastq.gz | Fastqsanger.gz | |||
| SRR18364023_subreads.fastq.gz | Fastqsanger.gz | |||
| SRR18364024_subreads.fastq.gz | Fastqsanger.gz | |||
| SRR18364025_subreads.fastq.gz | Fastqsanger.gz | |||
| SRR18364026_subreads.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 26 |
Similar Datasets
Project description:Targeted DNA sequencing approaches will improve how the size of short tandem repeats is measured for diagnostic tests and pre-clinical studies. The expansion of these sequences causes dozens of disorders, with longer tracts generally leading to a more severe disease. In addition, interruptions are sometimes present within repeats and can alter disease manifestation. Despite advances in methodologies, determining repeat size and identifying interruptions in targeted sequencing datasets remains a major challenge. This is because standard alignment tools are ill-suited for the repetitive nature of these sequences. To address this, we have developed Repeat Detector (RD), a deterministic profile weighting algorithm for counting repeats in targeted sequencing data. We tested RD using blood-derived DNA samples from Huntington’s disease (HD) and Fuchs endothelial corneal dystrophy patients sequenced using either Illumina MiSeq or Pacific Biosciences single-molecule, real-time sequencing platforms. RD was highly accurate in determining repeat sizes of 609 HD blood-derived samples and did not require prior knowledge of the flanking sequences or their polymorphisms within the patient population. We demonstrate that RD can be used to identify individuals with repeat interruptions and may provide a measure of repeat instability within an individual. RD is therefore highly versatile and may find applications in the diagnosis of expanded repeat disorders and the development of novel therapies.
2022-03-22 | GSE199005 | GEO
Project description:Expanded CAG/CTG repeats underlie thirteen neurological disorders, including myotonic dystrophy type 1 (DM1) and Huntington’s disease (HD). Upon expansion, CAG/CTG repeat loci acquire heterochromatic characteristics. This observation raises the hypothesis that repeat expansion provokes changes to higher-order chromatin conformation and thereby affects both gene expression in cis and the genetic instability of the repeat tract. Here we tested this hypothesis directly by performing 4C sequencing at the DMPK and HTT loci from DM1 and HD patient-derived cells. Surprisingly, chromatin contacts remain unchanged upon repeat expansion at both loci. This was true for expanded alleles with different DNA methylation levels and CTCF binding. Repeat tract sizes ranging from 15 to 1,700 repeats displayed strikingly similar chromatin interaction profiles. Moreover, the ectopic insertion of an expanded CAG repeat tract did not change the three-dimensional chromatin conformation of the surrounding genomic region. Our findings argue that extensive changes in heterochromatic properties are not enough to alter chromatin conformation at expanded CAG/CTG repeat loci. We conclude that 3D chromatin conformation is unlikely to drive repeat expansions or changes in gene expression in expanded CAG/CTG repeat disorders. This SuperSeries is composed of the SubSeries listed below.
2020-04-07 | GSE148185 | GEO
Project description:Bisulfite sequencing was performed on GM04604 (UN-B), GM06077 (DM1-A), and GM04648 (DM1-B) patient cells to determine the levels of CpG methylation present at two CTCF sites closely flanking the CTG repeats of DMPK.
2020-04-07 | GSE148177 | GEO
Project description:RNA-seq on proliferating myoblasts of the DM11 line carrying 13 and 2600 CTG repeats in the DMPK gene, compared to their genome-edited counterparts without both the 13 and 2600 CTG repeat or just lacking the 2600 CTG repeat.
2019-04-11 | GSE127296 | GEO
Project description:Expanded CAG/CTG repeats underlie thirteen neurological disorders, including myotonic dystrophy type 1 (DM1) and Huntington’s disease (HD). Upon expansion, CAG/CTG repeat loci acquire heterochromatic characteristics. This observation raises the hypothesis that repeat expansion provokes changes to higher-order chromatin conformation and thereby affects both gene expression in cis and the genetic instability of the repeat tract. Here we tested this hypothesis directly by performing 4C sequencing at the DMPK and HTT loci from DM1 and HD patient-derived cells. Surprisingly, chromatin contacts remain unchanged upon repeat expansion at both loci. This was true for expanded alleles with different DNA methylation levels and CTCF binding. Repeat tract sizes ranging from 15 to 1,700 repeats displayed strikingly similar chromatin interaction profiles. Moreover, the ectopic insertion of an expanded CAG repeat tract did not change the three-dimensional chromatin conformation of the surrounding genomic region. Our findings argue that extensive changes in heterochromatic properties are not enough to alter chromatin conformation at expanded CAG/CTG repeat loci. We conclude that 3D chromatin conformation is unlikely to drive repeat expansions or changes in gene expression in expanded CAG/CTG repeat disorders.
2020-04-07 | GSE148176 | GEO
Project description:The genetic cause of Myotonic Dystrophy Type 1 (DM1) is the expansion of unstable CTG-repeats in the 3´ untranslated region of the DMPK gene. Therapeutic gene editing for treatment of monogenic diseases could in principle remove definitively the disease-causing genetic defect. Here we describe the application of the CRISPR/Cas9 strategy to remove the CTG-expansion in the DMPK gene in myogenic cells derived from a DM1 patient that is heterozygous for the expansion. The efficacy of on-target genomic events was assessed by performing long-read DNA sequencing (Oxford Nanopore Technologies) after applying Cas9-mediated target enrichment of the Regions Of Interest (ROI), enabling the simultaneous analysis (a) of cuts by both sgRNAs resulting in the effective excision of the CTG expansion, (b) of cuts induced only by a single sgRNA, (c) of the potential occurrence of aberrant events such as inversions, and (d) the existence of non-edited sequences, within the same sample.
2025-02-26 | GSE279054 | GEO
Project description:Huntingtons disease (HD) is a devastating neurodegenerative disease, with out effective treatment. Despite significant advances, our understanding of how an expanded CAG repeat in the amino terminus of the large ubiquitously expressed HD gene product remains incomplete. Augmented adult neurogenesis in response to acute and chronic injury, including Huntingtons disease, has been demonstrated, but its role development, disease, and recovery is largely unknown, as are the factors controlling it. The HD gene product, huntingtin (htt) is know to interact with a number of transcription factors which subsequently influence gene expression. Understanding the factors involved in controlling neurogenesis in response to disease would bridge a significant knowledge gap and have tremendous therapeutic potential. We propose to identify transcripts responsible for CAG repeat facilitated neurogenesis. Our hypothesis is that expanded CAG repeats in the Huntingtons disease gene facilitates neurogenesis by altering transcription of genes critical in neurogenesis. We have developed a model in which mouse embryonic stem cells (ESC) with expanded CAG repeats have facilitated neurogenesis. In this model more ESC with expanded CAG repeats transition to neuronal precursors and then develop into mature neurons more rapidly than control ESC. We propose to compare the gene expression profiles between ESC with expanded CAG repeats and control ESCs on days 4 and 6 of neuronal differentiation. Initial studies indicate that key transcriptional differences are occurring at these time points. Control ECS and a an ESC line with150 CAG repeats will be differentiated in triplicate, and RNA isolated form each replicate. It is anticipated that comparison of gene expression between the control and CAG repeat lines at each time point will identify transcripts involved in CAG repeat facilitated neurogenesis. Observed differences at day 4 may be more relevant to the transition from ESC to neuronal precursor whereas differences at day 6 may be more relevant to the neuronal precursor to neuron transition. Keywords: time-course
2007-12-04 | GSE9760 | GEO
Project description:Expansion of the CAG/CTG repeats in functionally unrelated genes is a causative factor in many inherited neurodegenerative disorders, including Huntington's disease (HD), spinocerebellar ataxias (SCAs) and myotonic dystrophy type 1 (DM1). Despite many years of research, the mechanism responsible for repeat instability is unknown, and recent findings indicate the key role of DNA repair in this process. The repair of DSBs induced by genome editing tools results in the shortening of long CAG repeats in yeast models. Understanding this mechanism is the first step to developing a therapeutic strategy based on controlled shortening of repeats. The aim of this study was to characterize Cas9-induced DSB repair products in the endogenous HTT locus in human cells and to identify factors affecting the formation of specific types of mutations. The location of the cleavage site and its sequence affect the outcome of DNA repair. DSBs within CAG repeats result in shortening of the repeats in frame in ~90% of products. The mechanism of this contraction involves MRE11-CTIP and RAD51 activity and extensive DNA end resection reaching ~5000 bp. We demonstrated that a DSB located upstream of CAG repeats induces polymerase theta-mediated end joining, resulting in deletion of the entire CAG tract. Furthermore, using unbiased proteomic analysis, we identified novel factors that may be involved in CAG sequence repair.
2024-11-04 | PXD044960 | Pride
Project description:HuntingtonÂs disease (HD) is a devastating neurodegenerative disease, with out effective treatment. Despite significant advances, our understanding of how an expanded CAG repeat in the amino terminus of the large ubiquitously expressed HD gene product remains incomplete. Augmented adult neurogenesis in response to acute and chronic injury, including HuntingtonÂs disease, has been demonstrated, but its role development, disease, and recovery is largely unknown, as are the factors controlling it. The HD gene product, huntingtin (htt) is know to interact with a number of transcription factors which subsequently influence gene expression. Understanding the factors involved in controlling neurogenesis in response to disease would bridge a significant knowledge gap and have tremendous therapeutic potential. We propose to identify transcripts responsible for CAG repeat facilitated neurogenesis. Our hypothesis is that expanded CAG repeats in the HuntingtonÂs disease gene facilitates neurogenesis by altering transcription of genes critical in neurogenesis. We have developed a model in which mouse embryonic stem cells (ESC) with expanded CAG repeats have facilitated neurogenesis. In this model more ESC with expanded CAG repeats transition to neuronal precursors and then develop into mature neurons more rapidly than control ESC. We propose to compare the gene expression profiles between ESC with expanded CAG repeats and control ESCs on days 4 and 6 of neuronal differentiation. Initial studies indicate that key transcriptional differences are occurring at these time points. Control ECS and a an ESC line with150 CAG repeats will be differentiated in triplicate, and RNA isolated form each replicate. It is anticipated that comparison of gene expression between the control and CAG repeat lines at each time point will identify transcripts involved in CAG repeat facilitated neurogenesis. Observed differences at day 4 may be more relevant to the transition from ESC to neuronal precursor whereas differences at day 6 may be more relevant to the neuronal precursor to neuron transition.
2008-06-16 | E-GEOD-9760 | biostudies-arrayexpress
Project description:Three-dimensional chromatin interactions remain stable upon CAG/CTG repeat expansion
| PRJNA623390 | ENA