Search Results - EGA European Genome-Phenome Archive

Integration of human pancreatic islet genomic data refines regulatory mechanisms at Type 2 Diabetes susceptibility loci

Human genetic studies have emphasised the dominant contribution of pancreatic islet dysfunction to development of Type 2 Diabetes (T2D). However, limited annotation of the islet epigenome has constrained efforts to define the molecular mechanisms mediating the, largely regulatory, signals revealed by Genome-Wide Association Studies (GWAS). We characterised patterns of chromatin accessibility (ATAC-seq, n=17) and DNA methylation (whole-genome bisulphite sequencing, n=10) in human islets, generating high-resolution chromatin state maps through integration with established ChIP-seq marks. We found enrichment of GWAS signals for T2D and fasting glucose was concentrated in subsets of islet enhancers characterised by open chromatin and hypomethylation, with the former annotation predominant. At several loci (including CDC123, ADCY5, KLHDC5) the combination of fine-mapping genetic data and chromatin state enrichment maps, supplemented by allelic imbalance in chromatin accessibility pinpointed likely causal variants. The combination of increasingly-precise genetic and islet epigenomic information accelerates definition of causal mechanisms implicated in T2D pathogenesis.

Study EGAS00001002592

A combined circulating tumor DNA and protein biomarker-based liquid biopsy for the earlier detection of pancreatic cancer

The earlier diagnosis of cancer is one of the keys to reducing future cancer deaths. Here we describe our efforts to develop a non-invasive, blood test for the detection of pancreatic ductal adenocarcinoma. We combined blood tests for KRAS gene mutations with carefully thresholded protein biomarkers to determine whether the combination of these markers was superior to any single marker. The cohort tested included 221 patients with resectable pancreatic ductal adenocarcinoma and 185 control patients without known cancers. KRAS mutations were detected in the plasma of 66 patients (30%) and every mutation found in the plasma was identical to that subsequently found in the patients' primary tumor (100% concordance). The use of KRAS in conjunction with two thresholded protein biomarkers (CA19-9 and prolactin) increased the sensitivity to 67%. Only one of the 185 plasma samples from the control cohort were positive for any of the three markers (99.5% specificity). This combinatorial approach may prove useful for the earlier detection of many cancer types.

Study EGAS00001002444

Description and determinants of the faecal resistome and microbiome of farmers and slaughterhouse workers: a metagenome-wide cross-sectional study.

Within this study, we extracted DNA of 194 stool samples of persons living or working on pig and broiler farms (54 pig farmers, 24 broiler farmers), 70 pig slaughterhouse workers and 46 control subjects (Lifelines population living in the Northern parts of the Netherlands, and without recent antimicrobial use and occupational livestock contact). Total DNA was sequenced and metagenomic analysis was performed. Subsequently, the faecal resistomes and microbiomes were described and analysed (doi: 10.1016/j.envint.2020.105939). Highlights study: • Food chain workers are exposed to antimicrobial resistant (AMR) bacteria in livestock. • We describe faecal resistomes and microbiomes of farmers and slaughterhouse workers. • Faecal AMR gene loads in pork exposed workers exceed those in broiler farmers/controls. • Resistome and microbiome differences are shown between and within occupational groups. • On-farm working hours and working/living on a pig farm determine the faecal resistome. • Contact with livestock may be a determinant for human AMR gene carriage. This study is part of the EFFORT project: http://www.effort-against-amr.eu/.

Study EGAS00001003944

HCA_Female_Reporductive_Adult_WSSS_RNA

Cell atlas of the human placenta The Human Cell Atlas initiative is an ambitious global research effort which aims to describe every cell in the human body across all developmental stages to generate a reference map to accelerate progress in science and medicine particularly relating to human development and disease. The initiative is led by investigators based at the Wellcome Sanger Institute and the Broad Institute of MIT and Harvard and funding support from the Wellcome and NIH. This specific project will assess human development. We aim to interrogate the cellular composition and molecular regulators underpinning development and maturation through single cell RNA-sequencing/spatial transcriptomics and computational algorithms to predict cellular developmental trajectories and cell-cell interactions. We will subsequent validate these findings in situ using allied imaging technologies e.g. immunohistochemistry and RNAscope and in vitro culture of human intestinal organoids (HIOs). This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/

Study EGAS00001004210

Genomic and functional fidelity of small cell lung cancer patient-derived xenografts

Small cell lung cancer (SCLC) patient-derived xenografts (PDXs) can be generated from biopsies or circulating tumor cells (CTCs), though scarcity of tissue and low efficiency of tumor growth have previously limited these approaches. Applying an established clinical-translational pipeline for tissue collection and an automated microfluidic platform for CTC-enrichment, we generated 17 biopsy-derived PDXs and 17 CTC-derived PDXs in a two-year timeframe, at efficiencies of 89% and 38%, respectively. Whole exome sequencing showed that somatic alterations are stably maintained between patient tumors and PDXs. Early-passage PDXs maintain the genomic and transcriptional profiles of the founder PDX. In vivo treatment with etoposide and cisplatin (EP) in 30 PDX models demonstrated greater sensitivity in PDXs from EP naïve patients, and resistance to EP corresponded to increased expression of a MYC gene signature. Finally, serial CTC-derived PDXs generated from an individual patient at multiple time points accurately recapitulated the evolving drug sensitivities of that patient’s disease. Collectively, this work highlights the translational potential of this strategy.

Study EGAS00001002853

HCA_Placenta_Adult_Vento_RNA

The Human Cell Atlas initiative is an ambitious global research effort which aims to describe every cell in the human body across all developmental stages to generate a reference map to accelerate progress in science and medicine particularly relating to human development and disease. The initiative is led by investigators based at the Wellcome Sanger Institute and the Broad Institute of MIT and Harvard and funding support from the Wellcome and NIH. This specific project will assess human development. We aim to interrogate the cellular composition and molecular regulators underpinning development and maturation through single cell RNA-sequencing/spatial transcriptomics and computational algorithms to predict cellular developmental trajectories and cell-cell interactions. We will subsequent validate these findings in situ using allied imaging technologies e.g. immunohistochemistry and RNAscope and in vitro culture of human intestinal organoids (HIOs). This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/

Study EGAS00001004069

MethCORR: DNA Methylation-based Characterization, Classification and Prognostication of Colorectal Cancer using Archival Formalin-fixed, Paraffin-embedded Tissue

Transcriptional characterization and classification has potential to resolve the inter-tumor heterogeneity of colorectal cancer (CRC) and improve patient management. Yet, robust transcriptional profiling is difficult using formalin-fixed, paraffin-embedded (FFPE) samples, which complicates testing in clinical and archival material. We present MethCORR, an approach that allows uniform molecular characterization and classification of fresh-frozen and FFPE samples. MethCORR identifies genome-wide correlations between RNA expression and DNA methylation in fresh-frozen samples. This information is used to infer gene expression information in FFPE samples from their DNA methylation profiles. MethCORR was applied to methylation profiles from 877 fresh-frozen and FFPE samples and comparative analysis identified the same two major subtypes in four independent cohorts. Furthermore, subtype-specific prognostic biomarkers that better predicted relapse-free survival (HR=2.66, 95% CI [1.67-4.22], P<0.001) than TNM staging and MSI status were identified and validated using DNA methylation-specific PCR assays. The MethCORR approach is general, and may be similarly successful for other cancer types.

Study EGAS00001004293

Single-cell analysis of airway samples identifies immune cell activation correlating with COVID-19 disease severity

To investigate the immune response and mechanisms associated with severe COVID-19, we performed single-cell RNA-seq on nasopharyngeal and bronchial samples from 19 clinically well-characterized patients with moderate or critical disease and from 5 healthy controls. We identified airway epithelial cell types and states vulnerable to SARS-CoV-2 infection. In COVID-19 patients, epithelial cells showed an average threefold increase in expression of the SARS-CoV-2 entry receptor ACE2, which correlated with interferon signals by immune cells. Compared with moderate cases, critical cases exhibited stronger interactions between epithelial and immune cells, as indicated by ligand–receptor expression profiles, and activated immune cells , including inflammatory macrophages expressing CCL2, CCL3, CCL20, CXCL1, CXCL3, CXCL10, IL8, IL1B and TNF . The transcriptional differences in critical cases compared with moderate cases likely contribute to clinical observations of heightened inflammatory tissue damage, lung injury and respiratory failure. Our data suggest that pharmacologic inhibition of the CCR1 and/or CCR5 pathways may suppress immune hyperactivation in critical COVID-19.

Study EGAS00001004481

Genetic and epigenetic variation at regulatory regions contribute to cancer evolution under endocrine treatment

Comprehensive profiling of hormone-dependent breast cancer (HDBC) has identified hundreds of protein-coding alterations contributing to cancer initiation, but only a handful have been linked to endocrine therapy resistance, potentially contributing to 40% of relapses. If other mechanisms underlie the evolution of HDBC under adjuvant therapy is currently unknown. In this work, we employ integrative functional genomics to dissect the contribution of cis-regulatory elements (CREs) to cancer evolution by focusing on 12 megabases of non-coding DNA, including clonal enhancers, gene promoters, and boundaries of topologically associating domains. Massive parallel perturbation in vitro reveals context-dependent roles for many of these CREs, with a specific impact on dormancy entrance and endocrine therapy resistance9. Profiling of CRE somatic alterations in a unique, longitudinal cohort of patients treated with endocrine therapies identifies non-coding changes involved in therapy resistance. Overall, our data uncover actionable transient transcriptional programs critical for dormant persister cells and unveil new regulatory nodes driving evolutionary trajectories towards disease progression.

Study EGAS00001006340

Proteogenomics reveals two distinct biological pilocytic astrocytoma subgroups

Pilocytic astrocytoma (PA) is the most common pediatric brain tumor and driven by aberrant MAPK signaling, typically mediated by BRAF alterations. While five-year overall survival rates exceed 95%, tumor recurrence constitutes a major clinical challenge in incompletely resected tumors despite chemotherapeutic or radiation based therapies. Therefore, we used proteogenomics to discern the biological heterogeneity of PA to improve classification of this tumor entity and identify novel therapeutic targets. Our proteogenomics approach integrates RNA sequencing and LC/MS-based proteomic profiling data from a cohort of 58 confirmed, primary PA samples. An integrative genomics approach was conducted to discern the biological heterogeneity of PA and to identify aberrant pathway activation in these biological subgroups. In summary, Pilocytic astrocytomas segregate into two groups where younger patients are significantly associated with Group 1. Importantly, we validate the two distinct biological subgroups in two non-overlapping cohorts. The biological heterogeneity seen here may improve biological classification and reveal novel therapeutic targets specifically useful for non-resectable tumors with high risk of recurrent or progressive disease.

Study EGAS00001006402

Genomic analysis and evolutionary modeling of breast and larynx cancer, based on specimens from Polish population

We explore the genomic characteristics of the original dataset of breast and larynx cancer specimens of several cell types from the collection of the Department of Applied Radiology of the Maria Sklodowska-Curie National Research Institute of Oncology, Krakow (Poland) Branch and Institute of Human Genetics Polish Academy of Sciences. DNA from paired tissue samples from primary tumor locations and concurrent metastasis to regional lymph nodes was sequenced and matched to controls. A range of genomic analyses was carried out, such as estimation of variant allele frequencies (VAF) and copy number variation (CNV). They show that subsets of variants from primary tumors are present in metastatic lymph nodes and that the CNV pattern is similar, but not identical to that known in the literature. In addition to that, we fit the VAF data to theoretical site frequency spectra predicted by multiple models found in the literature. Analysis suggests existence of secondary advantageous subclones arising on the clonal background as well as of a number of neutral or slightly deleterious passenger mutations.

Study EGAS00001006456

scRNASeq of human innate lymphoid cells from different compartments

Group 1 innate lymphoid cells (ILCs) comprise a heterogeneous family of cytotoxic natural killer (NK) cells and ILC1s. We identifiy a population of “liver-type” ILC1s with transcriptional, phenotypic, and functional features distinct from those of conventional and liver-resident NK cells as well as from other previously described human ILC1 subsets. LT-ILC1s were CD49a+CD94+CD200R1+, expressed the transcription factor T-BET, do not express the activating receptor NKp80, or the transcription factor EOMES. Similar to NK cells, liver-type ILC1s produce IFN-γ, TNF-α, and GM-CSF; however, liver-type ILC1s also produce IL-2 and lack perforin and granzyme B. Liver- type ILC1s are expanded in cirrhotic liver tissues, and they can be produced from blood-derived ILC precursors in vitro in the presence of TGF-β1 and liver sinusoidal endothelial cells. Cells with similar signature and function can also be found in tonsil and intestinal tissues. Collectively, our study identifies and classifies a population of human cross-tissue ILC1s.

Study EGAS00001006847

RNA sequencing of CCO- and CCO+ human hepatocytes

RNAseq data from Passman et al 2023. Clonal CCO-deficient hepatocyte patches and nearby CCO-proficient hepatocytes were identified in morphologically normal human livers and sampled at varying distances along the PT-CV axis. Samples are named according to their location within the liver lobule, with "PT" denoting samples abutting the portal triad, "CV" denoting samples abutting the central hepatic vein, and "Mid" sampled acquired midway between these structures. Normal human liver is thought to be generally quiescent, however clonal hepatocyte expansions have been observed but neither their cellular source nor their expansion dynamics have been determined. Knowing the hepatocyte cell of origin, and their subsequent dynamics and trajectory within the human liver will provide an important basis to understand disease-associated dysregulation. Here we use in vivo lineage tracing and a combination of methylation sequence analysis to demonstrate normal human hepatocyte ancestry. We exploit next generation mitochondrial sequencing to determine hepatocyte clonal expansion dynamics across spatially-distinct areas of laser-capture microdissected clones, in tandem with computational modelling in morphologically-normal human liver.

Study EGAS00001006984

Preeclampsia InterPregGen Consortium: Whole Genome Sequencing of 100 unrelated Kazakhs (DNA samples from the Scientific Center of Obstetrics, Gynecology and Perinatology, Almaty, Kazakhstan; Gulnara Svyatova, Principal Investigator

Preeclampsia (PE) is a syndrome affecting pregnant mothers and fetus/babies characterised by hypertension and proteinuria, and is a leading cause of maternal and fetal death and of premature births worldwide. The InterPregGen Consortium was funded by a European Framework 7 (FP7) grant and grew out of the WTCCC3 GWAS comparing ~2000 UK PE mothers with ~6000 common UK controls. The EGAS00001000417 study data is whole genome sequencing of 100 unrelated Kazakhs in order to impute genotypes into PE cases and controls from Kazakhstan and to provide genetic data and infrastructure for future genetic studies in Kazakhstan and Central Asia more generally and to fill a gap in worldwide information as Central Asia is not adequately represented in available genomic data. This study is one component of the InterPregGen FP7 project. DNA samples for this component were collected by InterPregGen Consortium collaborators at the Scientific Center of Obstetrics, Gynecology and Perinatology, Almaty, Kazakhstan (Gulnara Svyatova, Principal Investigator)

Study EGAS00001000417

Pan Prostate Cancer Group data

The Pan Prostate Cancer Group intends to provide breakthrough advances from the analysis of a very large series of Whole Genome DNA data, contributed by many of the leading scientists and clinicians working in prostate cancer genomics generating Whole Genome DNA Sequence (WGS) data from prostate cancer patients. The accumulated data, collected and compared in a common format including common storage, re-analysis through a single pipeline, and investigation to achieve a variety of scientific goals, are presented in this series. This project will provide a global framework for the future analysis of even larger series of genomes as costs of DNA sequencing, storage, and sequence analysis decrease. In addition to these WGS data from different clinical categories, ethnicities, levels of aggressiveness, and disease managed by different treatments with information linked to long-term clinical follow up, we intend to add additional layers of data, including transcriptome and methylation data. The current data series focuses primarily on the analysis of WGS data. For further information, please refer to https://panprostate.org/, and The Pan Prostate Cancer Group Data Sharing Policy, EGAP00001003712.

Study EGAS00001002876

Intratumoral Heterogeneity and Clonal Evolution Induced by HPV Integration.

The human papillomavirus (HPV) genome is integrated into host DNA in most HPV-positive cancers, but the consequences for chromosomal integrity are unknown. Continuous long-read sequencing of oropharyngeal cancers and cancer cell lines revealed a unique form of structural variation, termed heterocateny here, characterized by heterogeneous, interrelated, and repetative patterns of concatemerized virus and host DNA segments. Evidence of heterocateny was detected in extrachromosomal and/or intrachromosomal DNA in all cases. Unique breakpoint sequences shared across structurally heterogeneous virus-host concatemers within each cancer facilitated stepwise reconstruction of their evolution from a common molecular ancestor. This analysis revealed that unstable virus and virus-host concatemers in ecDNA or integrated form mediate insertion into and excision from chromosomes, capture, rearrangement, and rolling-circle amplification of host DNA, and chromosomal rearrangements. The data indicate that heterocatena is driven by the dynamic, aberrant replication and recombination of an oncogenic DNA virus, thereby extending known consequences of HPV integration to include promotion of intra-tumoral heterogeneity and clonal evolution.

Study EGAS00001006652

GDAP - Genome Diversity in Africa Project (2021-02-12)

The Genomic Diversity in Africa Project (GDAP) started with the plan to develop a genomic resource from African populations, characterise genomic diversity and population history, and facilitate clinical studies in Africa. Currently, 25 individuals from 24 ethnolinguistic groups have been whole-genome sequenced at high depth totalling 585 individuals. An additional 41 individuals have been sequenced with 10X Genomics libraries. At this stage, the initial curation of this dataset has been finished and we are performing the analysis in coordination with our collaborators. The current state of the GDAP represents a very diverse panel of African populations that maximizes geographical and ethnic variation and represents a great starting point to achieve the aforementioned goals. However, southern sub-Saharan countries, Bantu speakers and hunter gatherer groups are currently underrepresented, despite being crucial to understand the evolutionary history of the continent. After extensive effort to collate studies documentation, we finally have the opportunity to sequence 600 new individuals from these groups, including countries as Gabon, Rwanda and Zambia, and address these deficiencies. We aim to proceed with the same strategy: to sequence at high depth 25 individuals with standard PCR free libraries, with 2 additional individuals with 10X Genomics Chromium libraries per ethnolinguistic group. The former allows a good representation of variants down to low frequency in any given population, and the latter allows accurate phasing and the analysis of structural variation. By including these new populations, we want to investigate three crucial questions in African history in addition to the initial objectives: the Bantu expansion, the evolutionary history of hunter gatherers and the transatlantic slave trade. Additionally, the expanded dataset will help us better discover the genetic variation present in Africa and characterize the African pangenome. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/ . This dataset contains all the data available for this study on 2021-02-12.

Dataset EGAD00001006965

Somatic mutation and selection at epidemiological scale - Sanger_NanoSeq_RandD

Bottleneck sequencing of human tissue including neurons, cord blood, sperm This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/. As we age, many tissues become colonised by microscopic clones carrying somatic driver mutations. Some of these clones represent a first step towards cancer whereas others may contribute to ageing and other diseases. However, our understanding of the clonal landscapes of human tissues, and their impact on cancer risk, ageing and disease, remains limited due to the challenge of detecting somatic mutations present in small numbers of cells. Here, we introduce a new version of nanorate sequencing (NanoSeq), a duplex sequencing method with error rates of less than 5 per billion base pairs, which is compatible with whole-exome and targeted gene sequencing. Deep sequencing of polyclonal samples with single-molecule sensitivity enables the simultaneous detection of mutations in large numbers of clones, yielding accurate somatic mutation rates, mutational signatures and driver mutation frequencies in any tissue. Applying targeted NanoSeq to 1,042 non-invasive samples of oral epithelium and 371 samples of blood from a twin cohort, we found an unprecedentedly rich landscape of selection, with 46 genes under positive selection driving clonal expansions in the oral epithelium, over 62,000 driver mutations, and evidence of negative selection in some genes. The high number of positively selected mutations in multiple genes provides high-resolution maps of selection across coding and non-coding sites, a form of in vivo saturation mutagenesis. Multivariate regression models enable mutational epidemiology studies on how carcinogenic exposures and cancer risk factors, such as age, tobacco or alcohol, alter the acquisition and selection of somatic mutations. Accurate single-molecule sequencing has the potential to unveil the polyclonal landscape of any tissue, providing a powerful tool to study early carcinogenesis, cancer prevention and the role of somatic mutations in ageing and disease.

Dataset EGAD00001015624

The Environmental Determinants of Diabetes in the Young Study (TEDDY)

Study Overview The Environmental Determinants of Diabetes in the Young (TEDDY) Study is a longitudinal study that investigates genetic and genetic-environmental interactions, including gestational events, childhood infections, dietary exposures, and other environmental factors after birth, in relation to the development of islet autoimmunity and type 1 diabetes (T1D). A consortium of six clinical centers assembled to participate in the development and implementation of the study to identify environmental triggers for the development of islet autoimmunity and T1D in genetically susceptible individuals. Beginning in 2004, the TEDDY study screened over 400,000 newborns for high-risk HLA-DR, DQ genotypes from both the general population and families already affected by T1D. The TEDDY study enrolled around 8,676 participants across six clinical centers worldwide (Finland, Germany, Sweden and three in the United States) in the 15-year prospective follow-up. Participants are followed every three months for islet autoantibody (IA) measurements with blood sampling until four years of age and then at least every six months until the age of 15. After the age of four, autoantibody positive participants continue to be followed at three month intervals and autoantibody negative participants are followed at six-month intervals. In addition to the analysis of autoantibodies, additional data and sample collection are performed at each visit. Parents collect monthly stool samples in early childhood. The parents also fill out questionnaires at regular intervals in connection with study visits and record information about diet and health status in the child's TEDDY Book between visits. Continued long-term follow-up of the currently active TEDDY participants will provide important scientific information on early childhood diet, reported and measured infections, vaccinations, and psychosocial stressors that may contribute to the development of type 1 diabetes and islet autoimmunity. Additional information on the TEDDY study is available in the following articles: Rewers et al., 2008, PMID: 19120261 and Hagopian et al., 2006, PMID: 17130573. Details of the TEDDY protocol can be found in Hagopian et al., 2011, PMID: 21564455. TEDDY data currently available in dbGaP include: gene expression, SNPs, exome, microbiome (gut, nasal, and plasma), RNA sequencing, and whole genome sequencing. For more information on TEDDY Study version history please refer to TEDDY Study dbGaP README File. ImmunoChip SNP DNA from whole blood samples on study participants and their family members (mothers, fathers, and siblings) was obtained and used for SNP genotyping. Genotyping was performed by the Center for Public Health Genomics at the University of Virginia using the Illumina ImmunoChip SNP array, which contains around 196,000 SNPs from 186 regions associated with 12 autoimmune diseases (Hadley et al., 2015, PMID: 26010309). Data cleaning and validation included the removal of subjects with a low call rate (< 5% SNPs missing) and differences in reported sex and prior genotyping at the TEDDY HLA laboratory. Additionally, SNPs with a low call rate or Hardy-Weinberg equilibrium P value < 10-6, except for chromosome 6 due to HLA eligibility requirements, were removed from the final dataset (Törn et al., 2015, PMID: 25422107).TEDDY-T1DExome ArrayDNA from whole blood samples on study participants and their family members (mothers, fathers, and siblings) was obtained and used for genotyping. Genotyping was performed by the University of Virginia using the Illumina TEDDY-T1DExome array. The TEDDY-T1DExome array is a custom chip that contains 550,601 markers from the Infinium CoreExome-24 v1.1 BeadChip and an additional 90,214 tagSNPs specifically selected by the TEDDY investigators based on their associations with nutrients, vitamins, type 2 diabetes, autoimmune diseases, body-mass index, or other exposures and phenotypes measured by TEDDY study.The Illumina GenTrain2 algorithm was used for genotype calling. Sample quality control metrics included sample call rate, heterozygosity rate and concordance of gender between the information reported and genotyped. Gene Expression The TEDDY study collected peripheral blood for the extraction of total RNA from enrolled children starting at 3 months of age, and then at 3 month intervals up to 48 months and then biannually. Total RNA was extracted using a high throughput (96-well format) extraction protocol using magnetic (MagMax) beads technology at the TEDDY RNA Laboratory, Jinfiniti Biosciences in Augusta, GA. Purified RNA (200 ng) was further used for cRNA amplification and labeling with biotin using Target Amp cDNA synthesis kit (Epicenter catalog no. TAB1R6924). Labeled cRNA was hybridized to the Illumina HumanHT-12 Expression BeadChips based on the manufacturer's instructions. The HumanHT-12 Expression BeadChip provides coverage for more than 47,000 transcripts and known splice variants across the human transcriptome. Microbiome The TEDDY microbiome study aimed to characterize the longitudinal development of the microbiome, including bacteria, viruses and other microorganisms in the gut, plasma, and nasal cavity of prediabetic and diabetic subjects compared to autoantibody negative non-diabetic subjects. Stool samples used were collected monthly from 3 to 48 months, after which stool samples were collected every 3 months. Nasal swab samples were collected every 3 months starting at 9 months of age until 48 months, after which nasal swabs were collected every 6 months. Plasma samples were collected every 3 months starting at 3 months of age until 48 months, after which plasma samples were collected every 6 months. If the subject was autoantibody positive at 48 months then they remained on the 3 month collection interval for nasal swab and plasma samples. Samples underwent 16s rRNA gene sequencing, DNA and viral RNA metagenomics shotgun sequencing, and sequencing of the internal transcribed spacer (ITS) regions. Additional information on the TEDDY microbiome data is available in the following articles: Vatanen et al., 2018, PMID: 30356183, Stewart et al., 2018, PMID: 30356187, and Vehik et al., 2020, PMID: 31792456. RNA Sequencing The TEDDY study aimed to characterize the transcriptome in subjects with islet autoimmunity and type 1 diabetes compared to matched control subjects. Peripheral blood was collected to extract total RNA from enrolled children starting at 3 months of age, and then at 3 month intervals up to 48 months and then biannually. Total RNA was extracted using a high throughput (96-well format) extraction protocol using magnetic (MagMax) beads technology at the TEDDY RNA Laboratory, Jinfiniti Biosciences in Augusta, GA. Purified RNA was then sent to the Broad Institute for the generation of the TEDDY RNA sequencing (RNA-Seq) data. The RNA samples were prepped using Superscript III reverse transcriptase and Illumina's TruSeq Stranded mRNA Sample Prep Kit. The TruSeq libraries were run on the Illumina HiSeq2500 platform. Whole Genome Sequencing The TEDDY study aimed to conduct deep whole genome sequencing and examine the genomic variations in subjects with islet autoimmunity and type 1 diabetes compared to matched autoantibody negative and non-diabetic children. DNA from whole blood was obtained from TEDDY children for whole genome sequencing. The WGS data were generated on the Illumina HiSeq X Ten system.

Study phs001442

Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT-BioLINCC)

Data Access NOTEPlease refer to the "Authorized Access" section below for information about how access to the data from this accession. Access differs from many other dbGaP accessions. BiospecimensAccess to Biospecimens is through the NHLBI Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC). Biospecimens from TOPCAT include Buffy Coat, DNA, Plasma, Serum, Urine, and Whole Blood. Please note that use of biospecimens in genetic research is subject to a tiered consent. Objectives The TOPCAT trial evaluated the effectiveness of aldosterone antagonist therapy in reducing cardiovascular mortality, aborted cardiac arrest, and heart failure hospitalization in patients who have heart failure with preserved systolic function. Background Many patients with heart failure have a normal, or near-normal, left ventricular ejection fraction (LVEF). Such patients share similar signs and symptoms as patients who have heart failure and a reduced LVEF, as well as an impaired quality of life and a poor prognosis. However, at the time of TOPCAT, the benefit of medical therapies for heart failure were limited to those with a reduced LVEF. Due to a lack of favorable evidence from clinical trials, clinical guidelines offered no specific recommendations for the management of heart failure in patients with preserved LVEF, except for attention to coexisting conditions. Among patients with heart failure and a reduced LVEF and those with myocardial infarction complicated by heart failure and left ventricular dysfunction, mineralocorticoid receptor antagonists have been shown to be effective in reducing overall mortality and hospitalizations for heart failure. In small mechanistic studies involving patients with heart failure and preserved left ventricular function, mineralocorticoid receptor antagonists improved measures of diastolic function. However, rigorous testing was needed regarding their effect on clinical outcomes in patients with preserved LVEF. Therefore, the TOPCAT trial was initiated to determine whether treatment with spironolactone, an aldosterone antagonist, would improve clinical outcomes in patients with symptomatic heart failure and a relatively preserved LVEF. Participants A total of 3445 participants were enrolled, with 1722 assigned to the spironolactone group and 1723 assigned to the placebo group. Among these, 2464 participants were enrolled via the hospitalization stratum and 981 were enrolled via the BNP stratum. Design TOPCAT was a phase 3, multicenter, international, randomized, double-blind, and placebo controlled trial. Eligible participants were randomly assigned to receive either spironolactone or placebo in a 1:1 ratio. Randomization was stratified according to whether the patient met the criterion for previous hospitalization or BNP elevation. The baseline visit included assessment of socio-demographics, physical characteristics, medical history, lifestyle factors, laboratory measures, electrocardiography variables and health-related quality of life and functional status. Study drugs were initially administered at a dose of 15 mg once daily, which was increased as tolerated to a maximum of 45 mg daily during the first four months after randomization. Subsequent dose adjustments were made as required and subjects continued to receive other treatments for heart failure and co-existing illnesses. Measurement of potassium and creatinine levels was required within 1 week after a change in the study-drug dose and at each scheduled study visit. Follow-up visits to monitor symptoms, medications, and events and to dispense study drug were scheduled every four months during the subject's first year on the study, and every six months thereafter. The mean follow-up interval was 3.3 years in each study group. Repository blood and urine samples were collected at the baseline and 1 year visits from consenting subjects. The primary endpoint was a composite of cardiovascular mortality, aborted cardiac arrest or hospitalization for the management of heart failure. Secondary endpoints included all-cause mortality, hospitalization for heart failure management, new onset of diabetes mellitus or atrial fibrillation, and quality of life. A subset of subjects also participated in the Echocardiography or Echocardiography and Vascular Stiffness ancillary studies. Echocardiography, and additionally tonometry in the Echocardiography and Vascular Stiffness study, were performed at baseline and at either 12 or 18 months following randomization. If the subject was already enrolled in the TOPCAT trial at the time the ancillary study was initiated, but had not yet reached the 18 month visit, baseline was determined via a retrospective analysis performed on any echocardiographic images completed within 60 days prior to TOPCAT enrollment and no tonometry was performed if applicable. Conclusions In patients with heart failure and a preserved ejection fraction, treatment with spironolactone did not significantly reduce the incidence of the primary composite outcome of death from cardiovascular causes, aborted cardiac arrest, or hospitalization for the management of heart failure. However, the drug reduced the secondary endpoint of heart failure hospitalization incidence.

Study phs003665

Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Using an Impedance Valve and Early Versus Delayed Analysis (PRIMED) (ROC-PRIMED-BioLINCC)

Accessing Data: Please refer to “Authorized Access” below regarding accessing data through the BioData Catalyst ecosystem. The data from this accession is not available for download through dbGaP.Objective: The purpose of this study was to examine two different treatments during a cardiac arrest that occurs outside of the hospital and whether either or both treatments would increase the number of people who lived to hospital discharge with satisfactory functional status. The first treatment involved using a device called the Impedance Threshold Device (ITD). The other treatment involved the amount of CPR given before the emergency medical services (EMS) providers first looked at the heart rhythm to determine if a shock is needed.Background: Out-of-hospital cardiac arrest is a common and lethal problem with a low survival rate, leading to an estimated 330,000 deaths each year in the United States and Canada. The traditional approach to out-of-hospital cardiac arrest has been to emphasize early analysis of cardiac rhythm, with delivery of defibrillatory shocks, if indicated, as quickly as possible. It has been suggested, however, that many participants may benefit from a period of CPR before the first analysis of rhythm.The impedance threshold device (ITD) is designed to enhance venous return and cardiac output during CPR by increasing the degree of negative intrathoracic pressure. Previous studies have suggested that the use of an ITD during CPR may improve survival rates after cardiac arrest. This effect is achieved by preventing the passive inflow of air into the chest during chest recoil between chest compressions without impeding active ventilation. The ITD has been found to improve hemodynamics, the perfusion of vital organs, and neurologically intact survival in studies in animals. The results of small, short-term clinical trials have suggested that the ITD can increase systolic blood pressure during resuscitation and improve short-term survival rates. Participants: In the ITD study, 4,345 participants were assigned to sham ITD and 4,373 to active ITD, while in the early versus later rhythm analysis, 5,290 participants were assigned to early cardiac rhythm analysis, and 4,643 were assigned to later cardiac rhythm analysis. This study qualified for exception from informed consent required for emergency research.Design: Most participants were enrolled simultaneously in both the early analysis versus later analysis component and the active ITD versus sham ITD component of the trial.The use of an active ITD was compared with that of a sham ITD in participants at 10 ROC sites in the United States and Canada. Participants, investigators, study coordinators, and all care providers were unaware of the treatment assignments. EMS personnel were trained in ITD function, proper use of the ITD, and all aspects of protocol implementation, with an emphasis on the optimal performance of CPR according to local guidelines. The first EMS responders to arrive at the scene of the arrest who were equipped with a randomly assigned ITD (active or sham) attached the device between the ventilation bag and face mask or between the bag and an advanced airway. Responders were encouraged to implement use of the device within 5 minutes after their arrival or as soon as clinically possible. Each of the 10 participating ROC centers was also divided into approximately 20 clusters. All episodes of cardiac arrest in a cluster were randomly assigned to one CPR strategy; after a set period of time, ranging from 3 to 12 months, all episodes in that cluster were then assigned to the other strategy. Participants in the early-analysis group were assigned to receive 30 to 60 seconds of chest compressions and ventilations (sufficient time to place defibrillator electrodes) before electrocardiographic (ECG) analysis, and those in the late-analysis group were assigned to receive 3 minutes of chest compressions and ventilations before ECG analysis. The start and stop times for CPR were recorded by the responders, and the information was supplemented by the recording of defibrillator time. Conclusions: All 10 sites halted enrollment in November 2009 when the data and safety monitoring board recommended termination because interim analysis showed that the findings were not likely to change with continuation of the study. Neither use of the ITD nor the amount of CPR given before cardiac rhythm analysis significantly improved survival with satisfactory function (i.e., a score of ≤3 on the modified Rankin scale) among participants with out-of-hospital cardiac arrest receiving standard CPR. There were also no significant differences in the secondary outcomes, including rates of return of spontaneous circulation on arrival at the emergency department, survival to hospital admission, and survival to hospital discharge.

Study phs003825

The Finland-United States Investigation of NIDDM Genetics (FUSION) Tissue Biopsy Study

The Finland-United States Investigation of NIDDM Genetics (FUSION) study is a long-term effort to identify genetic variants that predispose to type 2 diabetes (T2D) or that impact the variability of T2D-related quantitative traits (QTs). Most of the variants associated with T2D and related traits (glucose and insulin, anthropometrics, lipids) through genome-wide association studies (GWAS) occur in non-coding regions, suggesting a strong regulatory component to disease susceptibility. Regulatory element activity is often tissue-specific, which further complicates discovery of the causal/functional variation. Therefore, there is a critical need to identify the appropriate cell type, regulatory elements, target genes, and causal variants(s) in T2D-relevant tissues. We hypothesize that a subset of T2D and related variants alter gene expression regulation in skeletal muscle and adipose tissue - two major insulin target tissues and play key roles in insulin resistance. To that end, our study contains a comprehensive survey of genomics, epigenomics and transcriptomics in skeletal muscle and adipose tissue from individuals with glucose tolerance categories ranging from normal to T2D.For this FUSION Tissue Biopsy Study, we obtained RNA-Seq, microRNA (miRNA)-Seq, and DNA methylation (methyl)-Seq data on biopsy samples from 331 individuals from across the range of glucose tolerance: 124 normal glucose tolerance (NGT), 77 impaired glucose tolerance (IGT), 44 impaired fasting glucose (IFG), and 86 newly-diagnosed T2Ds. Participants completed two study visits, two weeks apart. First visits comprised most of the clinical phenotyping, including four-point OGTT (fasting, and 30, 60, and 120 minute post-load); BMI, WHR; lipids; blood pressure; and many other variables. Participants also completed FUSION health history, medication, and lifestyle questionnaires. On the second visit, we obtained ~250mg vastus lateralis skeletal muscle, ~750mg abdominal subcutaneous adipose, and a ~5x15mm section of abdominal skin. Visits were completed in March 2013. RNA isolation is ongoing in the Collins laboratory at the NIH, RNA and miRNA sequencing at the NIH Intramural Sequencing Center (NISC), and genotyping at the Center for Inherited Disease Research (CIDR). Individual-level data is available here for the 306 individuals who consented to data deposit. To focus on evaluation of gene expression and its regulation in skeletal muscle, we analyzed mRNA extracted from vastus lateralis skeletal muscle obtained from 271 of the 331 individual subjects from Finland, along with genome-wide genotypes. Individual-level data is available here for the 250 subjects who consented to the use of their data.Release phs001048.v2.p1 adds muscle data for an additional 42 subjects and data from adipose tissue for 276 subjects. Total RNA was isolated using Trizol extraction in the Collins laboratory at the NIH. The mRNA was poly-A selected, 24-plex libraries were generated using the Illumina TruSeq directional mRNA-seq library protocol and RNA sequencing was performed on HiSeq2000 sequencers using 101bp paired-end reads at NISC. miRNA libraries were prepared from total RNA from 296 muscle and 270 adipose samples, pooled and sequenced 50bp single-end reads on Illumina HiSeq2500. Data for 272 muscle and 251 adipose samples are available here for individuals with consent for data deposit. DNA was extracted from blood in the Collins laboratory, and genotyping on the Illumina Omni2.5M array was performed at CIDR. Genotypes were imputed using the HRC 2016 reference panel. In order to assess regions of open chromatin in skeletal muscle, we obtained muscle tissue from a commercial provider to perform ATAC-seq; these samples were sequenced at the University of Michigan DNA Sequencing Core.Release phs001048.v3.p1 adds single-nucleus (sn) RNA-seq and ATAC-seq data in 287 skeletal muscle samples out of the original 331 individuals. Individual-level data is available here for the 265 subjects who consented to the use of their data. The frozen tissue biopsy samples were processed in ten batches, each consisting of 40-41 samples. These batches were organized using a randomized block design to protect against experimental contrasts of interest including cohort, age, sex, BMI among others. Samples in each batch were pulverized, pooled together followed by nuclei isolation. The nuclei were processed on the 10X Genomics Chromium platform separately for snATAC-seq and snRNA-seq (v. 3.1 chemistry for snRNA-seq).Release phs001048.v4.p1 adds additional phenotypes and provides some corrections to several previous phenotypes.

Study phs001048

Submitter Portal

Submitter Portal The Submitter Portal does not support array submissions! Please refer to the array documentationAny new objects registered in the Submitter Portal will not be available for use in an array submission For further information please check our Submission FAQs, submission quickguide as well as submission terms! The metadata submission process can be difficult and time-consuming. For this reason, the EGA has developed the Submitter Portal, a tool that was created to offer a simplified and user-friendly method of registering metadata. Our portal provides features that are intended to make the input of metadata easier, ensuring that your data is registered correctly and effectively. Our page is divided into logical sections and includes a helpful video instruction to further assist you as you complete the submission process. With the Submitter Portal, you can rest assured that the submission of your data is in good hands. Submitter Portal Index Previous steps Access to Submitter Portal Start a Submission Take The Tour Tutorial Previous steps Create your EGA account To submit data, you first need to create your EGA user. Then, once your account has been verified by the Help Desk team, you will be able to request a submitter role and send the EGA Data Processing Agreement (DPA). In the case you already have an EGA account, or an ega-box (submission account), you can skip this step. Upload your files Please note that all your files must be encrypted using the Crypt4GH tool before upload them.As soon as you are assigned with a submitter role and added your public key to your profile, you will be able to connect to the EGA inbox and upload your files. Understand the EGA metadata schema It's crucial to comprehend the EGA metadata schema, a set of rules that specify how data is organised, described, and shared inside the EGA, in order to get the most out of this resource. Learn all about EGA metadata schema! Register your DAC and policy There are two objects in the EGA metadata schema that are registered in a separate portal. All DACs and policy objects are registered using the DAC Portal, a tool developed by EGA to help data controllers manage their data stored at the EGA. You can find relevant information in the DAC Portal Guide. Access to Submitter Portal 1. Request Submitter Role Once you have created your EGA user, request a Submitter Role and complete relevant information such as submission type and size. 2. Signature of the Data Processing Agreement The Data Processing Agreement (DPA) signed by CRG and EMBL-EBI (Joint Data Processors for the EGA) can be downloaded to the submitter for its signature. Further information related to the DPA can be in the Privacy Notice section. The DPA should be signed by a legal representative of the submitter with power of attorney/appointment duly authorised to sign contracts on behalf of the institution. The submitter will return a fully-executed copy of the DPA to us. Please note that due to the high volume of submissions to EGA the DPA is non-negotiable. Once you have completed all the information and attached the DPA signed, send your Submitter request and the EGA Helpdesk Team will validate it and send a confirmation to start submitting your metadata. Start a Submission The steps below will show you how to start a submission and are accompanied with a tutorial and the Take the tour of Submitter Portal. 1. Login Go to the Submitter Portal interface and log in using your EGA account credentials. 2. Create a submission The Submitter Portal interface will show you any already existing open submission. To start a new submission click on “Create a Submission”.In this phase you have the option to add any collaborator(s) as well as their permissions (“Read only” or “Read & Write”). If you want to invite all the collaborators from a previous submission, you can add them by selecting said submission.In the event that the submission has been closed, you will need to reopen it. To do this, you will need to modify one of the objects in the submission, for example, copy and paste the title. Once the submission is open, you can add a collaborator. Further information can be found in the Submission Tour 3. Create Study Click on add Study and complete the form with the relevant information. The fields with an asterisk (*) are mandatory. Further information can be found in the Submission Tour4. Create Sample Sample registration can be done either individually or in batch by using a template. Batch upload: download the template and complete it with information about the sequencing samples. Upload the samples.csv and the sample will be created.Add single sample: complete the mandatory fields with the metadata information of your sample. Further information can be found in the Submission Tour5. Create Experiment Register an experiment with information about the sequencing methods, protocols and machines. Experiments generate the connection between samples and study. Further information can be found in the Submission Tour6. Create Run Samples, experiments and files are linked through runs. To register a run, you will be asked to select the appropriate experiment and the file format. Run registration can be done either individually or in batch by using a template. Batch upload: download the template and complete it with the sample - file linkage. Upload the run.csv and the runs will register.As the INBOX is a directory, bear in mind to include the file path (/). Example: /filename.c4gh. Add single run: select the file format, sample and experiment from the drop box. For re-using submitted samples, please use the EGA accession ID (EGANXXX). Please note that files must be uploaded in your inbox before linking your files and samples. Further information can be found in the Submission Tour7. Create Analysis Analysis should be only used for BAM/BAI or CRAM/CRAI pair, VCF and phenotype linkage to samples. The analysis is an EGA specific metadata object that links samples to files. This object also stores some metadata about your experiments, such as the experiment type, genome reference, or the platform used. **If only BAM or CRAM alignment files are submitted but not the original unaligned FASTQ files, then please make sure that the BAM or CRAM files also contain the unaligned reads. This is critical to enable primary re-analysis and re-alignment of the dataset using new tools or future genome assemblies.** Start by selecting the samples to be linked to the file, and then populate the required attribute fields. Please be aware of the existence of mandatory fields that must be populated.When populating the chromosome field (mandatory), please select the chromosomes from the checkbox. Please take in consideration that EGA allows for the re-use of any registered metadata. Therefore, a previously registered study or samples can be referenced for the analysis in the current data submission.Further information can be found in the Submission Tour 8. Create Dataset Dataset contains the collection of runs/analysis data files subjected to controlled access by being associated with a Policy. Complete the mandatory fields such as title, description, type and policy. Please, take in consideration that DAC and Policy must be registered in advance in the DAC Portal. Similar to other metadata objects, you can re-use previous runs or analyses, using their EGA accessions IDs (runs - EGAR, analyses - EGAZ). Further information can be found in the Submission Tour 9. Finalise submission Once the files are ingested please delete them from your SFTP INBOX before finalising your submission. This will prevent the files from reappearing in your Submitter Portal Inbox. Once you have completed your submission, click on the Finalise button, and schedule an estimated release date. Afterwards, your submission will be sent to Helpdesk for approval. Please note that once the Helpdesk has approved your submission, you will receive the identifiers for your data. See the Frequently Asked Questions (FAQ) for more information. 10. Update closed submission If you want to append more file to a closed submission, you will need to re-open the submission where the dataset was registered. Find the Submission: go to the Submitter Portal Menu -> Datasets section and find the submission id (EGA0XXX). Reopen the submission where the dataset is located: to reopen a submission, you must edit any object within the submission. For example, you can copy and paste the title. Take The Tour The Submitter Portal Take The Tour is a visual guidance of all the steps described previously about how to start a submission. Tutorial In this tutorial we will show you how to use the Submitter Portal to register your metadata. Please note the video focuses on the run-based submission (for raw files - fastq - and aligned data - BAM/CRAM) and analysis-based submission (for your BAM/BAI pairs, variation -VCF - and phenotype files).

Documentation submission/metadata/submission/sequencing-phenotype/submitter-portal

Therapeutic Trial of Potassium and Acetazolamide in Andersen-Tawil Syndrome

Andersen-Tawil syndrome (ATS) is an ion channel disorder that causes episodes of muscle weakness and potentially life-threatening heart arrhythmias. The majority of ATS cases are caused by a mutation in the KCNJ2 gene, which is linked to potassium channels in the heart, brain, and skeletal muscle; other cases are presumed to be caused by an undetermined gene lesion. To date, the treatment for ATS has been largely anecdotal, and no treatments have been formally assessed in a controlled clinical trial. This study will determine whether potassium supplements and/or acetazolamide, which is a diuretic medication, affect the duration of muscle weakness and heart rhythm abnormalities in people with ATS. Participation in this study will last about 11 months. Participants will first attend a 3-day inpatient visit that will include a medical history, physical examination, blood work, heart rhythm testing by an electrocardiogram (ECG) and Holter monitor, strength testing, a health questionnaire, and daily potassium supplementation. Participants will also track the number and length of weakness episodes that they experience while in the hospital. On the last day of the inpatient visit, participants will be provided with multiple bottles containing either potassium or placebo. Participants will then return home for an 18-week treatment period that will consist of six 3-week-long treatments of either potassium or placebo, with the treatment schedule being randomly determined. Upon completing the first 18-week treatment period, participants will attend a second 3-day inpatient visit that will include the same tests and procedures as the first. The only difference will be that participants will receive acetazolamide along with potassium. This will be followed by a second 18-week treatment period that will consist of six 3-week-long treatments of either acetazolamide or placebo. At the end of the second treatment period, participants will fill out another health questionnaire. Throughout both 18-week treatment periods, participants will phone in daily to track any muscle or heart problems. They will also provide blood samples on a weekly basis. At Weeks 2, 5, 8, 11, 14, and 17 of both treatment periods, participants will wear a Holter monitor for 24 hours and then mail it in. A final outpatient visit will occur 8 weeks after the end of the second treatment period and will include heart rhythm testing, muscle strength testing, and blood work.

Study phs001316

Palindromic Amplification of The ERBB2 Oncogene in HER2-Positive Breast Cancer

DNA Inverted Repeats as an At-risk Motif for Palindromic Gene Amplificatio defines oncogene amplification that is configured as a series of inverted duplications (palindromic gene amplification). There are several, recurrently amplified oncogenes throughout the human genome. However, it remains unclear whether this recurrent amplification is solely a manifestation of increased fitness resulting from random amplification mechanisms, or if genomic locus-specific amplification mechanism plays a role. In this study, we show that the ERBB2 oncogene at 17q12 is susceptible to palindromic gene amplification in HER2-positive breast tumors. We investigated eight tumors in this study, of which five tumors were HER2-positive, and three tumors were HER2-negative. HER2-status was determined by clinical FISH tests. We applied three genomic approaches to investigate the amplification mechanism: (1) copy number analysis by array-CGH on the Affymetrix SNP6.0 platform (8 files), (2) sequencing of DNA libraries enriched with tumor-derived palindromic DNA (Genome-wide Analysis of Palindrome Formation, GAPF-seq) (8 files) and (3) unbiased whole genome sequencing (WGS) (1 file). These molecular data is made available in the dbGaP. Genomic studies using tumor DNA was approved under the Internal Institutional Review Board at the Cleveland Clinic (IRB07-136: EXEMPT: Chromosome Breakage and DNA Palindrome Formation). Specimens were obtained and methods were carried out under the auspices of IRB 7881 (Evaluation of Genetic and Molecular Markers in Patients with Breast Cancer). All patients consented to allow their cancer specimens to be used by researchers in an anonymized fashion. The consent form indicates that publication will take place without identifiers to protect the identity of any specific individual. We observed significant and enrichment of palindromic DNA within amplified ERBB2 genomic segments in four out of five HER2-positive tumors. None of three HER2-negative tumors showed such enrichment. Palindromic DNA was particularly enriched at amplification peaks and boundaries between amplified and normal copy-number regions. Thus, palindromic gene amplification shaped the amplified ERBB2 locus. The moderate enrichment of palindromic DNA throughout the amplified segments leads us to propose that the ERBB2 locus is amplified through a mechanism that repeatedly generates palindromic DNA, such as Breakage-Fusion-Bridge cycles. Our results reveal a potential interaction between local genomic environments and gene amplification mechanisms. This study is published under the title "Palindromic amplification of the ERBB2 oncogene in primary HER2-positive breast tumors" (PMID:28211519).

Study phs001261

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