Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA264832 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Interpreting the genomic and phenotypic consequences of copy number variation (CNV) is essential to understand the etiology of genetic disorders. Whereas deletion CNVs obviously lead to haploinsufficiency, duplications may cause disease through triplosensitivity, gene disruption, or gene fusion at breakpoints. The mutational spectrum of duplications has been studied at certain loci and in some cases these copy number gains are complex chromosome rearrangements involving triplications and/or inversions. However, the organization of clinically relevant duplications throughout the genome has not been investigated on a large scale. Here, we fine mapped 184 germline duplications (14.7 kb-25.3 Mb; median 532 kb) ascertained from individuals referred for diagnostic cytogenetics testing. We performed next-generation sequencing (NGS) and whole-genome sequencing (WGS) to sequence 130 breakpoints from 112 subjects with 119 CNVs and found that most (83%) were tandem duplications in direct orientation. The remainder were triplications embedded within duplications (8.4%), adjacent duplications (4.2%), insertional translocations (2.5%), or other complex rearrangements (1.7%). In addition, we predicted six in-frame fusion genes at sequenced duplication breakpoints. Four gene fusions were formed by tandem duplications, one by two interconnected duplications, and one by duplication inserted at another locus. These novel fusion genes could be related to clinical phenotypes and warrant further study. Though most duplications are positioned head-to-tail adjacent to the original locus, those that are inverted, triplicated, or inserted can disrupt or fuse genes in a manner that may not be predicted by conventional copy number analysis. Thus, interpreting the genetic consequences of duplication CNVs requires breakpoint-level analysis.
2014-10-25 | GSE62657 | GEO
Project description:Inverted duplications are a common type of copy number variation (CNV) in germline and somatic genomes. Large duplications that include many genes can lead to both neurodevelopmental phenotypes in children and gene amplifications in tumors. There are several models for inverted duplication formation, most of which include a dicentric chromosome intermediate followed by breakage-fusion-bridge (BFB) cycles, but the mechanisms that give rise to the inverted dicentric chromosome in most inverted duplications remain unknown. Here we have combined high-resolution array CGH, custom sequence capture, next-generation sequencing, and long-range PCR to analyze the breakpoints of 50 nonrecurrent inverted duplications in patients with intellectual disability, autism, and congenital anomalies. Sequence analysis of breakpoint junctions reveals a normal-copy disomic spacer between inverted and non-inverted copies of the duplication. Further, short inverted repeats are present at the boundary of the disomic spacer and the inverted duplication. These data support a mechanism of inverted duplication formation whereby a chromosome with a double-strand break intrastrand pairs with itself to form a “hairpin” intermediate that, after DNA replication, produces a dicentric inverted chromosome with a disomic spacer corresponding to the site of the hairpin. We also find evidence of short insertions and inversions at inverted duplication junctions, consistent with a DNA replication-based CNV mechanism. This process can give rise to inverted duplications adjacent to terminal deletions, inverted duplications juxtaposed to translocations, and inverted duplication ring chromosomes High resolution array CGH; two-color experiment, clinical patient vs. normal control gDNA; sex mis-matched
2013-04-03 | E-GEOD-45395 | biostudies-arrayexpress
Project description:Using array CGH and fiber-FISH, we found that several human T-ALL have tandem duplication of the MYB gene on one allele, we used microarray gene expression analysis to determine if increased MYB expression correlates with gene duplication Keywords: cell type comparison
2007-10-20 | GSE9342 | GEO
Project description:Inverted duplications are a common type of copy number variation (CNV) in germline and somatic genomes. Large duplications that include many genes can lead to both neurodevelopmental phenotypes in children and gene amplifications in tumors. There are several models for inverted duplication formation, most of which include a dicentric chromosome intermediate followed by breakage-fusion-bridge (BFB) cycles, but the mechanisms that give rise to the inverted dicentric chromosome in most inverted duplications remain unknown. Here we have combined high-resolution array CGH, custom sequence capture, next-generation sequencing, and long-range PCR to analyze the breakpoints of 50 nonrecurrent inverted duplications in patients with intellectual disability, autism, and congenital anomalies. Sequence analysis of breakpoint junctions reveals a normal-copy disomic spacer between inverted and non-inverted copies of the duplication. Further, short inverted repeats are present at the boundary of the disomic spacer and the inverted duplication. These data support a mechanism of inverted duplication formation whereby a chromosome with a double-strand break intrastrand pairs with itself to form a “hairpin” intermediate that, after DNA replication, produces a dicentric inverted chromosome with a disomic spacer corresponding to the site of the hairpin. We also find evidence of short insertions and inversions at inverted duplication junctions, consistent with a DNA replication-based CNV mechanism. This process can give rise to inverted duplications adjacent to terminal deletions, inverted duplications juxtaposed to translocations, and inverted duplication ring chromosomes
2013-04-03 | GSE45395 | GEO
Project description:Colorectal cancer (CRC) represents the third most common cancer worldwide. Next generation sequencing (NGS) appearance has allowed us to produce huge amount of data and, in order to fully exploit its usage, copy number variants (CVN) detection software have been developed. In this study, we analyze germline DNA whole-exome sequencing (WES) data from 38 families with strong CRC aggregation without alterations in known hereditary genes to detect rare candidate CNVs to CRC predisposition using ExomeDepth and CoNIFER tools. Variants shared between family members were compared to Database of Genomic Variants (DGV) catalogue and our Spanish database. CNVs finally selected were validated and segregation analysis were performed using Comparative Genome Hybridization (CGH). Gene expression arrays and qRT-PCR were conducted in both germline and tumor cDNA to check possible effects at transcription level. Immunohistochemistry (IHC) studies were also carried out. Whith this, 21 candidate CNV corresponding to 16 duplications and 5 deletions were detected by calling tools. After multiple filtering steps, only the duplication in chromosome 1 in family 7 stood out as interesting. Validation by CGH confirmed the duplication and correct family segregation. TTF2, TRIM45, VTCN1 and miR942 are embedded in chromosome 1 duplication. Expression studies pointed to TTF2 and miR942 overexpression in carriers, and tumor IHC showed TTF2 protein overexpression and underexpression of the TMEM158 protein. Also known as RIS1, TMEM158 is a predicted target of miR942 and has been claimed to be a candidate tumor-supressor. All in all, chromosome 1 duplication may correspond to the mutational event involved in CRC predisposition in the carrier family by overexpressing TTF2 and miR942, leading to TMEM158 underexpression. Keywords: colorectal cancer, next generation sequencing, copy number variant, duplication, predisposition.
2019-03-01 | GSE96597 | GEO
Project description:We here describe the first successful construction of a targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae. The targeted tandem chromosomal duplication was achieved by using strains that had 5M-bM-^@M-^YM-NM-^TpyrG upstream of the region targeted for tandem chromosomal duplication and 3M-bM-^@M-^YM-NM-^TpyrG downstream of the target region. Consequently, strains bearing a 210-kb targeted tandem chromosomal duplication near the centromeric region of chromosome 8 and strains bearing a targeted tandem chromosomal duplication of a 700-kb region of chromosome 2 were successfully constructed. The strains bearing the tandem chromosomal duplication were efficiently obtained from the regenerated protoplast of the parental strains. However, the generation of the chromosomal duplication did not depend on the introduction of double-stranded breaks (DSBs) by I-SceI. The chromosomal duplications of these strains were stably maintained after five generations of culture under non-selective conditions. The strains bearing the tandem chromosomal duplication in the 700-kb region of chromosome 2 showed highly increased protease activity in solid-state culture, indicating that the duplication of large chromosomal segments could be a useful new breeding technology and gene analysis method. A. oryzae strain bearing a 210-kb targeted tandem chromosomal duplication, A. oryzae strain bearing a 700-kb targeted tandem chromosomal duplication, and A. oryzae RIB40 (wild type strain), were cultivated in Polypeptone-dextrin medium. After 3 days cultivation, genomic DNAs from the samples were extracted, and array CGH analysis was carried out to confirm the chromosomal duplications in the strains.
2014-06-30 | E-GEOD-57246 | biostudies-arrayexpress
Project description:The study was carried out to identify copy number variations using array-CGH in family having three children affected with albinism (OCA1B) and the males were affected with ID. Agilent’s SureScan microarray scanner with SurePrint G3 Human CGH, 8x60K array platform was used for the study. The probes used for the experiment was approximately 60000 oligonucleotide, allowing detection of deletions above 200 Kb and duplication above 500 kb in entire human genome. CytoGenomics software used to carryout data analysis revealed CNVs in participants.
2021-12-03 | GSE190026 | GEO
Project description:Array CGH was performed to identify the breakpoints in 3 cases with deletions of 16p11.2p12.2 and 1 case with a duplication/triplication of 16p11.2p12.2.
2007-09-01 | E-TABM-286 | biostudies-arrayexpress
Project description:Balanced chromosome rearrangements (BCRs) can cause genetic diseases by disrupting or inactivating specific genes, and the characterisation of breakpoints in disease-associated BCRs has been instrumental in the molecular elucidation of a wide variety of genetic disorders. However, mapping chromosome breakpoints using traditional methods, such as in situ hybridization with fluorescent dye-labeled bacterial artificial chromosome clones (BAC-FISH), is rather laborious and time consuming. In addition, the resolution of BAC-FISH is often insufficient to unequivocally identify the disrupted gene. To overcome these limitations, we have performed shotgun sequencing of flow-sorted derivative chromosomes using ‘next generation’ (Solexa/Illumina) multiplex sequencing-by-synthesis technology. As shown here for three different disease-associated BCRs, the coverage attained by this platform is sufficient to bridge the breakpoints by PCR amplification, and this procedure allows to determine their exact nucleotide positions within few weeks. Its implementation will greatly facilitate large-scale breakpoint mapping and gene finding in patients with disease-associated balanced translocations. Keywords: Array CGH
2008-04-01 | GSE10115 | GEO
Project description:Using array CGH and fiber-FISH, we found that several human T-ALL have tandem duplication of the MYB gene on one allele, we used microarray gene expression analysis to determine if increased MYB expression correlates with gene duplication Keywords: cell type comparison RNA from 17 T-ALL cell lines
2007-10-19 | E-GEOD-9342 | biostudies-arrayexpress