ABSTRACT: Assays in bile duct cancer patients showed 984 CNVs in 306 CNV regions (CNVR) distributed throughout all 22 chromosomes. Bile duct cancer patients had a mean of 21.8 gains and 19.2 losses of genes, with an average of 35.9 CNVRs per patient. Frequent sites of gains were at chromosomes 22q11.22, 2p11.2-p.11.1, 14q32.33 and 17q12, whereas frequent sites of losses were at 19q12-q13.43. Investigation of CNV in 24 bile duct cancer tissue samples
Project description:Assays in bile duct cancer patients showed 984 CNVs in 306 CNV regions (CNVR) distributed throughout all 22 chromosomes. Bile duct cancer patients had a mean of 21.8 gains and 19.2 losses of genes, with an average of 35.9 CNVRs per patient. Frequent sites of gains were at chromosomes 22q11.22, 2p11.2-p.11.1, 14q32.33 and 17q12, whereas frequent sites of losses were at 19q12-q13.43.
Project description:Cell fate change involves significant genome reorganization, including change in replication timing, but how these changes are related to genetic variation has not been examined. To study how change in replication timing that occurs during reprogramming impacts the copy number variation (CNV) landscape, we generated genome-wide replication timing profiles of induced pluripotent stem cells (iPSCs) and their parental fibroblasts. A significant portion of the genome changes replication timing as a result of reprogramming, indicative of overall genome reorganization. We found that early and late replicating domains in iPSCs are differentially affected by copy number gains and losses, and that in particular CNV gains accumulate in regions of the genome that change to earlier replication during the reprogramming process. This differential relationship was present irrespective of reprogramming method. Overall, our findings reveal a functional association between reorganization of replication timing and the CNV landscape that emerges during reprogramming. Keywords: Expression profiling by array [Gene expression] We isolated RNA from normal human fibroblast derived iPS cells, normal human fibroblasts, and human embryonic stem cells for hybridization to the Affymetrix gene expression microarrays. [CNV] We isolated genomic DNA from iPSCs derived with retroviral and episomal vectors and their parental fibroblast cells for hybridization to the Affymetrix Genome-Wide Human SNP 6.0 Array.
Project description:Genomic structural variation is an important and abundant source of genetic and phenotypic variation. Here we describe the first systematic and genome-wide analysis of copy number variations (CNVs) in modern domesticated cattle using array comparative genomic hybridization (array CGH), quantitative PCR (qPCR) and fluorescent in situ hybridization (FISH). The array CGH panel included 90 animals from 11 Bos taurus, 3 Bos indicus and 3 composite breeds for beef, dairy or dual purpose. We identified over 200 candidate CNV regions (CNVRs) in total and 177 within known chromosomes, which harbor or are adjacent to gains or losses. These 177 high-confidence CNVRs cover 28.1 mega bases or ~1.07% of the genome. Over 50% of the CNVRs (89/177) were found in multiple animals or breeds and analysis revealed breed-specific frequency differences and reflected aspects of the known ancestry of these cattle breeds. Selected CNVs were further validated by independent methods using qPCR and FISH. Approximately 67% of the CNVRs (119/177) completely or partially span cattle genes and 61% of the CNVRs (108/177) directly overlap with segmental duplications. The CNVRs span about 400 annotated cattle genes that are significantly enriched for specific biological functions such as immunity, lactation, reproduction and rumination. Multiple gene families, including ULBP, have gone through ruminant lineage-specific gene amplification. We detected and confirmed marked differences in their CNV frequencies across diverse breeds, indicating that some cattle CNVs are likely to arise independently in breeds and contribute to breed differences. Our results provide a valuable resource beyond microsatellites and single nucleotide polymorphisms to explore the full dimension of genetic variability for future cattle genomic research. The custom aCGH chips that interrogated the whole genome CNVs were build for 90 cattles from diverse breeds, with Hereford L1 Dominette 01449 as refference sample.
Project description:Cell fate change involves significant genome reorganization, including change in replication timing, but how these changes are related to genetic variation has not been examined. To study how change in replication timing that occurs during reprogramming impacts the copy number variation (CNV) landscape, we generated genome-wide replication timing profiles of induced pluripotent stem cells (iPSCs) and their parental fibroblasts. A significant portion of the genome changes replication timing as a result of reprogramming, indicative of overall genome reorganization. We found that early and late replicating domains in iPSCs are differentially affected by copy number gains and losses, and that in particular CNV gains accumulate in regions of the genome that change to earlier replication during the reprogramming process. This differential relationship was present irrespective of reprogramming method. Overall, our findings reveal a functional association between reorganization of replication timing and the CNV landscape that emerges during reprogramming. 3 cell lines, all in duplicates
Project description:Tumors acquire somatic DNA copy number aberrations, leading to activation of oncogenes and inactivation of tumor suppressors. Many studies have focused on the analysis of single copy number aberrations and associated driver genes, but few studies have performed combinatorial analyses. We propose a genome-wide scoring framework to find mutually exclusive gains and losses. Mutually exclusive copy number aberrations can identify genes whose oncogenic function is redundant, either by functioning in the same pathway or in a parallel pathway. As one gene is aberrated the selective pressure for its partner is alleviated which leads to a mutually exclusive perturbation pattern. In a dataset of mouse models for invasive lobular carcinoma we found three mutually exclusive DNA amplifications, containing several well-known oncogenes: the Met proto-oncogene on chromosome 6, the cluster of Birc2, Birc3 and Yap1 genes on chromosome 9, and Nras on chromosome 3. Furthermore, gene expression or protein expression of these genes correlates very well with copy number data indicating that they are the target of the amplification. Although homologous amplifications in human tumors are rare, the mutual exclusivity of MET, BIRC/YAP1 and NRAS is maintained in a variety of cancer types. This suggests a novel function for YAP1 in the mitogen-activated signaling pathway by association with MET and NRAS, known players in this pathway. This function is independent to the propensity of YAP1 to cause Epithelial-to-Mesenchymal transition. aCGH data of 67 mouse mammary tumors from K14-Cre and WAP-Cre driven P53-F/F;Cdh1-F/F animals - tumor DNA hybridized against same-animal splenic DNA
Project description:Genome instability is a potential limitation to the research and therapeutic application of induced pluripotent stem cells (iPSCs). Observed genomic variations reflect the combined activities of DNA damage, cellular DNA damage response (DDR), and selection pressure in culture. To understand the contribution of DDR on the distribution of copy number variations (CNVs) in iPSCs, we mapped CNVs of iPSCs with mutations in the central DDR gene ATM onto genome organization landscapes defined by genome-wide replication timing profiles. We show that following reprogramming the early and late replicating genome is differentially affected by CNVs in ATM deficient iPSCs relative to wild type iPSCs. Specifically, the early replicating regions had increased CNV losses during retroviral reprogramming. This differential CNV distribution was not present after later passage or after episomal reprogramming. Comparison of different reprogramming methods in the setting of defective DNA damage response reveals unique vulnerability of early replicating open chromatin to retroviral vectors. We isolated genomic DNA from Ataxia-telangiectasia (A-T) iPSC cells derived from patient fibroblasts virus and episomal vectors, coresponding fibroblasts, normal human fibroblast derived iPSCcells, for hybridization to the Affymetrix Genome-Wide Human SNP 6.0 Array.
Project description:<p>Copy number variation (CNV) has been recognized as a major contributor to human genome diversity. It plays an important role in determining phenotypes and has been associated with a number of common and complex diseases. However the CNV data from diverse populations is rather limited. Here we report the first investigation of copy number variation (CNV) in the indigenous populations from Peninsular Malaysia. We genotyped 34 Negrito genomes from Peninsular Malaysia using the Affymetrix SNP 6.0 microarray and identified 62 putative novel CNVs, consisting of 25 gains and 37 losses. These CNVs appear unique to the Negrito population and were absent in the DGV, HapMap3 and Singapore Genome Variation Project (SGVP) datasets. Analysis of gene ontology revealed that genes within these CNVs were enriched in the immune system (GO:0002376), response to stimulus mechanisms (GO:0050896), as well as the metabolic pathways (GO:0001852). Copy number gains in CNVRs enriched with genes were significantly higher than the losses (P value <0.001). Therefore, in view of the small population size, relative isolation and semi-normadic lifestyles of this community, we speculate that these CNVs may be attributed to recent local adaptation of Negritos from Peninsular Malaysia.</p>
Project description:If copy number variants (CNVs) are predominantly deleterious, we would expect them to be more efficiently purged from populations with a large effective population size (Ne) than from populations with a small Ne. Malaria parasites (Plasmodium falciparum) provide an excellent organism to examine this prediction, because this protozoan shows a broad spectrum of population structures within a single species, with large, stable, outbred populations in Africa, small unstable inbred populations in South America and with intermediate population characteristics in South East Asia. We characterized 122 single-clone parasites, without prior laboratory culture, from malaria-infected patients in 7 countries in Africa, SE Asia and S. America using a high density SNP/CNV microarray. We scored 134 high-confidence CNVs across the parasite exome, including 33 deletions and 102 amplifications, which ranged in size from <500bp to 59kb, as well as 10,107 flanking, biallelic SNPs. Overall, CNVs were rare, small and skewed towards low frequency variants, consistent with the deleterious model. Relative to African and SE Asian populations, CNVs were significantly more common in S. America, showed significantly less skew in allele frequencies, and were significantly larger. On this background of low frequency CNV, we also identified several high-frequency CNVs under putative positive selection using an FST outlier analysis. These included known adaptive CNVs containing rh2b and pfmdr1, and several other CNVs (e.g. DNA helicase, and 3 conserved proteins) that require further investigation. Our data are consistent with a significant impact of genetic structure on CNV burden in an important human pathogen. SNP/CGH hybridisation of 175 malaria parasite samples
Project description:RNA-Sequencing was performed on mechanically dissociated, epithelial-enriched samples, of human extrahepatic biliary tissue from Gallbladder, Common Bile Duct, and Pancreatic Duct tissues. Sequencing was also performed on in vitro cultures of Organoid cell lines at passage 5 that were derived from human Gallbladder, Common Bile Duct, Pancreatic Duct, or Intrahepatic Bile Ducts.
Project description:Cell fate change involves significant genome reorganization, including change in replication timing, but how these changes are related to genetic variation has not been examined. To study how change in replication timing that occurs during reprogramming impacts the copy number variation (CNV) landscape, we generated genome-wide replication timing profiles of induced pluripotent stem cells (iPSCs) and their parental fibroblasts. A significant portion of the genome changes replication timing as a result of reprogramming, indicative of overall genome reorganization. We found that early and late replicating domains in iPSCs are differentially affected by copy number gains and losses, and that in particular CNV gains accumulate in regions of the genome that change to earlier replication during the reprogramming process. This differential relationship was present irrespective of reprogramming method. Overall, our findings reveal a functional association between reorganization of replication timing and the CNV landscape that emerges during reprogramming.