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• Somatic point mutation data from microsatellite unstable colorectal cancers

  Microsatellite instability (MSI) leads to accumulation of an excessive number of mutations in the genome, mostly small insertions and deletions. MSI CRCs, however, also contain more point mutations than microsatellite stable (MSS) tumors, yet they have not been as comprehensively studied. To identify candidate driver genes affected by point mutations in MSI CRC, we ranked genes based on mutation significance while correcting for replication timing and gene expression utilizing an algorithm, MutSigCV. Somatic point mutation data from the exome kit-targeted area from 24 exome sequenced sporadic MSI CRCs and respective normals, and 12 whole genome sequenced sporadic MSI CRCs and respective normals were utilized. The top 73 genes were validated in 93 additional MSI CRCs.

  Study EGAS00001003101

• Whole genome sequencing of 25 South African individuals with myasthenia gravis

  This study investigated the genetic basis of an ophthalmoplegic subphenotype of MG (OP-MG) which occurs in a proportion of myasthenics with juvenile symptom onset and African genetic ancestry. This OP-MG subphenotype is characterised by treatment resistant weakness of the extraocular muscles (EOMs) and the pathogenetic mechanism(s) underlying its development is unknown. The aim of this study was to use a hypothesis-generating genome-wide case-control analysis to identify candidate OP-MG susceptibility genes and pathways. Whole genome sequencing (WGS) was performed on 25 AChR-antibody positive myasthenic individuals of African genetic ancestry sampled from the phenotypic extremes: 15 with OP-MG (cases) and 10 individuals with control MG (EOM treatment-responsive).

  Study EGAS00001003462

• ABIS_1_MeDIP-seq

  We investigated changes in whole genome DNA-methylation in a group of 48 healthy five-year-old children differentiated by their hair cortisol levels. By combining this novel biomarker for chronic stress with methylated DNA immunoprecipitation sequencing (MeDIP-seq), we found that high cortisol were associated with a genome-wide decrease in DNA-methylation targeted to specific zinc finger transcription factor binding sites, repetitive elements and genes important for neurodevelopment and calcium transport. Large scale hypomethylation of repetitive regions, as well as a deficient calcium transport, have been reported in many stress related diseases, as well as in many cancers and biological aging. Thus our findings may aid in our understanding of how susceptibility to these diseases develops.

  Study EGAS00001001099

• A whole genome analysis of single fetal human stem cells from the liver and the intestine

  Mutations of embryonic and fetal origin have the potential to affect a large proportion of adult cells and may alter cancer predisposition or lead to genetic disease syndromes. We have recently shown that human adult-stem cells progressively acquire approximately 40 novel tissue-specific mutations per year throughout postnatal life. Prenatal mutation rates are as yet unknown. Here we determined genome-wide mutation patterns of single stem cells in human development by sequencing of clonally expanded intestinal and liver organoid cultures of 2nd trimester human foetuses. Our results show that mutation rates in fetal stem cells are significantly higher than in adult stem cells.

  Study EGAS00001002886

• EPIC arrays data for chemotherapy response project

  In this study, a total of 300 patients with MIBC receiving chemotherapy were included; 62 received NAC before cystectomy and 245 received first-line chemotherapy upon detection of locally-advanced (T4b) or metastatic disease. Treatment response, defined as pathological downstaging (< pTa,CIS,N0) after NAC or complete or partial response after first-line treatment (RECIST criteria). DNA methylation analysis was performed using DNA from 72 patients. We used 500 ng genomic DNA for bisulfite conversion followed by whole-genome amplification prior to hybridization to EPIC BeadChip (Illumina, San Diego, CA) overnight as described by the manufacturer and then scanned with the Illumina iSCAN system. Data provided here consist of 144 idat files.

  Study EGAS00001004515

• Epiclomal: probabilistic clustering of sparse single-cell DNA methylation data

  We present Epiclomal, a probabilistic clustering method arising from a hierarchical mixture model to simultaneously cluster sparse single-cell DNA methylation data and infer their corresponding hidden methylation profiles. Using synthetic and published single-cell CpG datasets we show that Epiclomal outperforms non-probabilistic methods and is able to handle the inherent missing data feature which dominates single-cell CpG genome sequences. Using a recently published single-cell 5mCpG sequencing method (PBAL), we show that Epiclomal discovers sub-clonal patterns of methylation in aneuploid tumour genomes, thus defining epiclones. We show that epiclones may transcend copy number determined clonal lineages, thus opening this important form of clonal analysis in cancer.

  Study EGAS00001003504

• RNA sequencing of undifferentiated sarcomas

  Undifferentiated sarcomas (USARCs) of adults are diverse, rare, and aggressive soft tissue cancers. Recent sequencing efforts have confirmed that USARCs exhibit one of the highest burdens of structural aberrations across human cancer. Here, we sought to unravel the molecular basis of the structural complexity in USARCs by integrating DNA sequencing, ploidy analysis, gene expression, and methylation profiling. We identified whole genome duplication as a prevalent and pernicious force in USARC tumorigenesis. Using mathematical deconvolution strategies to unravel the complex copy-number profiles and mutational timing models we infer distinct evolutionary pathways of these rare cancers. In addition, 15% of tumors exhibited raised mutational burdens that correlated with gene expression signatures of immune infiltration, and good prognosis.

  Study EGAS00001003291

• Mutational landscape of eccrine porocarcinoma (sweat gland tumour)

  Eccrine porocarcinoma (EP) is the most common form of sweat gland malignancy. The aetiology of EP is largely unknown. The current lack of data on somatic mutation patterns in EP hampers the development of effective therapies. We performed whole-exome sequencing in a well-characterized sample of 14 matched EP tumour/healthy surrounding tissue samples. Mutational profiling revealed a high overall median mutation rate. This was attributed to signatures of mutational processes related to ultraviolet (UV) exposure, APOBEC enzyme dysregulation, and defective homologous double-strand break repair. All of these processes cause genomic instability and are implicated in carcinogenesis. The analyses revealed alterations in the cancer driver genes and in crucial oncogenic pathways.

  Study EGAS00001004632

• Tumor microenvironment study of ovarian granulosa cell tumors

  Adult-type granulosa cell tumors (aGCT) are rare ovarian sex cord tumors with few 41 effective treatments for recurrent disease. The objective of this study was to compare global gene expression profiles and characterize the tumor microenvironment (TME) of primary and recurrent aGCTs in order to identify correlates of disease recurrence. Total RNA sequencing was performed on 24 pathologically confirmed, cryopreserved aGCT samples, including 8 primary and 16 recurrent tumors. A total of 31 differentially expressed genes were identified between primary and recurrent aGCT. TME analysis demonstrated significantly higher fractions of neutrophils and macrophages in recurrent tumors in conjunction with significantly lower fractions of cancer-associated fibroblasts and endothelial cells.

  Study EGAS00001006478

• Multiple Sclerosis risk variants regulate gene expression in innate and adaptive immune cells

  Each of at least 200 single nucleotide polymorphisms (SNPs) have been confirmed to be associated with individually small increases in the risk of Multiple Sclerosis (MS). A key function that could mediate SNP encoded MS risk is their regulatory effects on gene expression or splicing. Transcriptomic profiling was performed using Affymetrix gene-expression microarrays, using RNA extracted from purified human peripheral blood monocytes, CD4 and CD8 positive lymphocyte cells, B-lymphocyte cells and Natural Killer cells from 73 untreated MS cases and 97 healthy controls. Cis expression quantitative trait locus (eQTL) mapping studies were performed in each cell type separately to characterize MS risk loci associated with gene expression change.

  Study EGAS00001004087

• Identification and functional characterisation of a rare MTTP variant underlying familial non-alcoholic fatty liver disease

  We identified a rare causal variant in MTTP, c.1691T>C p.I564T (rs745447480) encoding microsomal triglyceride transfer protein (MTP) causing progressive non-alcoholic fatty liver disease with cirrhosis and hepatocellular carcinoma unrelated to metabolic syndrome, without manifestations of abetalipoproteinemia, in a four generation family with South Asian ancestry. Variant-expressing hepatocyte-like-cells (HLCs) derived from human induced pluripotent stem cells generated from homozygous donor skin fibroblasts had lower lipoprotein ApoB secretion, compared to wild type cells. Cytoplasmic triglyceride accumulation in HLCs triggered endoplasmic reticulum stress, secretion of pro-inflammatory mediators, production of reactive oxygen species, delineating the progression of disease associated with homozygosity for MTTP p.I564T

  Study EGAS00001005254

• Transcriptomic analysis of cell-of-origin CNS neuroblastoma, FOXR2 activated

  The transcription factor FOXR2 is the universal driver of childhood central nervous system neuroblastoma, FOXR2 activated (NB-FOXR2). NB-FOXR2 tumors arise exclusively in the brain hemispheres, and despite morphological similarities to other pediatric brain tumors, they are a molecularly distinct entity based on DNA methylation profiling. The cell-of-origin is unknown. Here, we profiled a cohort of rare NB-FOXR2 tumors by bulk and single-cell transcriptomics. Through systematic comparative analyses, we delineate tumor transcriptional states and candidate cell-of-origin. More broadly, we demonstrate systematic molecular profiling of childhood cancers to orient oncogenic targeting for in vivo modeling, a critical resource for the study of rare tumors and development of therapeutics.

  Study EGAS00001007247

• Distinct Stem Cell Identities Converge into Shared Erythroid Stress in ERCC6L2 Disease and Shwachman-Diamond Syndrome

  ERCC6L2 disease (ED) is a rare bone marrow failure syndrome caused by biallelic germline mutations in ERCC6L2. ED leads to accumulation of somatic TP53 mutations, myelodysplastic syndrome, and acute myeloid leukemia (AML) with erythroid predominance and poor prognosis. To delineate the transcriptomic events underlying delayed erythropoiesis and leukemic progression in ED, we leverage single-cell transcriptomics and single-cell TP53 genotyping of patient bone marrow across ED and Shwachman-Diamond syndrome. The dataset contains raw single-cell gene expression data (scRNA-seq), raw single-cell amplicon data (scAmp-seq), and curated metadata describing sample identity, cell populations, and disease classification. Related processed data will be available at ArrayExpress.

  Study EGAS50000001880

• 33 patients with Monoclonal Gammopathy of Undetermined Significance (MGUS)

  Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant precursor of multiple myeloma (MM) with a 1% risk of progression per year. Although targeted analyses have shown the presence of specific genetic abnormalities such as IGH translocations, RB1 deletion, 1q gain, hyperdiploidy or RAS genes mutations, little is known about molecular mechanism of malignant transformation. We have performed whole exome sequencing together with SNP array analysis in 33 flow-cytometry separated abnormal PC samples of MGUS patients to describe somatic gene mutations and chromosome changes at the genome-wide level. Non-synonymous mutations (NS-SNVs) and copy number alterations (CNAs) were present in 97.0% and in 63.6% of cases, respectively. Importantly, the number of somatic mutations was significantly lower in MGUS compared to MM (p<10-4) and we have identified 6 myeloma significantly mutated genes which are KRAS, NRAS, DIS3, HIST1H1E, EGR1 and LTB in the MGUS dataset. We also found a positive correlation with increasing chromosome changes and somatic mutations. IGH translocations were present in 27.3% of cases comprising t(4;14), t(11;14), t(14;16) or t(14;20) and were in a similar frequency to MM, which corresponded with primary lesion hypothesis. Data from this study showed MGUS is a genetically comprehensive disease, however overall genetic instability is significantly lower compared to MM.

  Dataset EGAD00001001901

• Targeted replication of LVOTO genes

  Non-syndromic cases of congenital heart defects (CHD) exhibit variable modes of inheritance (Mendelian and non-Mendelian). Several studies have identified strong candidates in humans by taking a candidate gene approach as well as by using whole exome next generation sequencing (NGS). So far these studies could only explain a minor fraction of the observed phenotype in humans, most of them in syndromic cases and no single study has focused on the subset of cases with left ventricular outflow tract obstruction (LVOTO). To discover novel disease-causing genes a large cohort of patients with LVOTO, approximately 100 cases, 25 families and 100 trios have been exome sequenced. This study based on NGS sequencing data yielded several known and novel compelling candidate genes, such as MYH6, NR2F2 and MYH11, but also novel ones, such as ITGB4. To evaluate the significance of our findings in a replication cohort we assembled another 1614 cases with an LVOTO phenotype from our collaborators in Toronto, Berlin and Amsterdam. Targeted resequencing in this additional cohort will help to find additional cases with mutations in the identified candidate genes to strengthen genotype-phenotype association. We will use control data from the INTERVAL project for case/control analyses The pulldowns will be performed as 24-plex ISC with 192 or greater indexes, and the sequencing will be performed with 192 samples per lane, requiring 9 lanes of sequencing.

  Dataset EGAD00001002212

• RNA-seq study of human long-term and short-term hematopoietic stem cells from umblical cord blood with lentiviral overexpression of S1PR3

  To investigate the molecular and biological pathways altered by S1PR3OE in human hematopoietic stem cells (HSC), we performed RNA-sequencing (RNA-seq) of LT- and ST-HSC 3 days after transduction with control or S1PR3 overexpression (OE) lentiviral vectors. LT-HSC and ST-HSC from 3 pool of CB lin- were FACS-purified, cells were prestimulated for 4 hours and transduced with lentiviral vectors. At day 3, 2000-5300 BFP+ cells were FACS-purified for RNA isolation with a PicoPure kit. We were able to isolate only 1600-1800 BFP+ cells from LT-HSC control samples as opposed to 4000-5400 BFP+ cells from S1PR3OE samples. Thus, we pooled all control BFP+ LT-HSC cells into one sample for RNA-seq analysis. BFP- LT-HSC from control vector transduction were purified from CB1 as an additional LT-HSC control. Nextera libraries generated from 10 ng RNA from 5 LT-HSC samples (2 controls, 3 S1PR3OE) and 6 ST-HSC samples (3 controls, 3 S1PR3OE) were subjected to 125 bp, paired-end RNA-sequencing on the Illumina HiSeq 2500 with an average of 50 million reads/sample at the Center for Applied Genomics, Sick Kids Hospital.

  Dataset EGAD00001006582

• Whole exome sequencing of a representative cohort of AML

  The Genomic DNA Clean & Concentrator kit (ZYMO Research) was used to remove EDTA from the DNA samples. Sample libraries were prepared using 100 ng of input according to the KAPA HyperPlus Kit (Roche) using Unique Dual Index adapters (Integrated DNA Technologies, Inc.). Exomes were captured using the SeqCap EZ MedExome (Roche Nimblegen) according to SeqCap EZ HyperCap Library v1.0 Guide (Roche) with the xGen Universal blockers – TS Mix (Integrated DNA Technologies, Inc.). The amplified captured sample libraries were paired-end sequenced (2x100 bp) on the Novaseq 6000 platform (Illumina) and aligned to the hg19 reference genome using the Burrows-Wheeler Aligner (BWA)3, v0.7.15-r1140.

  Dataset EGAD00001007580

• Targeted de novo phasing and long-range assembly by template mutagenesis

  Long-range sequencing with low error rate has been challenging. Sequence assembly and phasing usually require a high-quality reference genome for mapping, so working on highly-variable genomic regions or regions with no reference genome information would be difficult. In this study, we describe novel bench protocols and algorithms to obtain ultra-low-error-rate haplotype-phased sequence assemblies of regions 10 KB in length using a short-read sequencing platform that simultaneously solves the above two problems. We accomplish this by imprinting each template strand from a target region with a dense and unique mutation pattern. The mutation process randomly and independently converts ~50% of cytosines to uracils. Short-read sequencing libraries are made from both mutated and unmutated templates. A conservative de Bruijn graph approach seeds an assembly of the mutated templates, which we then extend by mapping paired-end reads. We next partition the template assemblies into two or more haplotypes after using the unmutated sequence library to recover almost all of the mutated bases. The final haplotype is assembled and corrected for residual template mutations and PCR errors. We obtain per-base-error rates below 10 9. We apply this method to a human family, correctly assembling and phasing three genomic intervals, including the highly polymorphic HLA-B gene.

  Dataset EGAD00001008444

• Mechanisms of Therapy Driven Clonal Evolution in Oncogenic RAS Mutant Relapsed Acute Lymphoblastic Leukemia

  Although multi-agent combination chemotherapy is curative in a significant fraction of childhood acute lymphoblastic leukemia (ALL) patients, 20% of cases relapse and most die due to chemo-refractory disease. Here we used whole-exome and whole-genome sequencing to analyze the mutational landscape and pattern of clonal evolution at relapse in pediatric ALL cases. These analyses showed that ALL relapses originate from a common ancestral precursor clone of the diagnosis and relapsed populations and frequently harbor mutations implicated in chemotherapy resistance. RAS-MAPK pathway activating mutations in NRAS, KRAS and PTPN11 were present in 24/55 (44%) cases in our series. Notably, while some cases showed emergence of RAS mutant clones at relapse, in others, RAS mutant clones present at diagnosis were replaced by RAS wild type populations. Mechanistically, functional dissection of mouse and human wild type Kras and mutant Kras (Kras G12D) isogenic leukemia cells demonstrated induction of methotrexate resistance, but also improved response to vincristine, in mutant Kras- expressing lymphoblasts. These results identify chemotherapy driven selection as a central mechanism of leukemia clonal evolution and pave the road for the development of tailored personalized therapies for the treatment of relapsed ALL.

  Study phs001072

• Developmental Mechanisms of Human Congenital Heart Disease in Subjects with 22q11.2 Deletion Syndrome (DiGeorge Syndrome/Velocardiofacial Syndrome)

  The study is designed to identify genetic modifiers of cardiovascular defects in subjects with 22q11.2 deletion syndrome (22q11.2DS), also known as DiGeorge syndrome or velo-cardio-facial syndrome. Affymetrix 6.0 arrays were processed on 1,480 subjects with known cardiovascular anomalies or with normal structures, all with 22q11.2DS. One sample is a duplicate so it was removed. There are 1,472 samples total of unrelated, de-identified, probands. Over 90% have the same sized 3 million base pair deletion flanked by low copy repeats (LCR22) A and D, while approximately 6% have nested A to B deletions. The rest have other nested deletions, that include a deletion in the vicinity of TBX1 (between LCR22 A and B). A subset of the data was used to identify copy number variations serving as modifiers. Some data were previously published by Dr. Emanuel's team at Children's Hospital of Philadelphia in PA, USA (PMID:26742502; PMID:4896312; PMID:25892112; PMID:4570279). The de-identified DNA data from unrelated subjects come from multiple research sites in the US and Europe as part of the International 22q11.2 Consortium and the International 22q11.2 Brain and Behavior Consortium.

  Study phs001339

• Studies in the Natural History and Pathogenesis of Childhood-Onset and Adult-Onset Idiopathic Inflammatory Myopathies

  The present study compares transcript and protein regulation in peripheral blood of adult and juvenile dermatomyositis (DM) patients vs. healthy control subjects to identify novel pathways in active patients under treatment. Whole blood data is submitted representing transcript and protein expression, including 14 adult DM and 11 juvenile DM (JDM) patients, and 11 healthy pediatric controls. Whole blood RNA was examined using Affymetrix Human U133 Plus 2.0, and whole blood protein measurements were obtained using SOMAscan Assay v3.2 aptamer-based DNA probes.Expression of 1,124 gene loci were significantly altered at the transcript or protein levels across DM or JDM, with 70 genes shared. A subset of interferon-stimulated genes was elevated. Innate immune markers specific to neutrophil granules and neutrophil extracellular traps were up-regulated in both DM and JDM. Pathway analysis revealed up-regulation of PI3K/AKT, ERK, and p38 MAPK signaling. Up-regulated components shared by DM and JDM included: cytokine:receptor pairs LGALS9:HAVCR2, LTF/NAMPT/S100A8/HSPA1A:TLR4, CSF2:CSF2RA, EPO:EPOR, FGF2/FGF8:FGFR; several Bcl-2 components; and numerous glycolytic enzymes. Pathways unique to DM included sirtuin signaling, aryl hydrocarbon receptor signaling, protein ubiquitination, and granzyme B signaling.

  Study phs003270

• Genetic Basis of Breast Cancer Resistance in BRCA1 Mutation Carrier

  Our study addressed a specific question in NCI RFA-CA-12-022: "What underlying causal events - e.g., genetic, epigenetic, biologic, behavioral, or environmental - allow certain individuals to survive beyond the expected limits of otherwise highly lethal cancers?". A germline mutation in BRCA1 (BRCA1+) is the most penetrant genetic predisposition for breast cancer. Nevertheless, a portion of BRCA1+ carriers does not develop breast cancer in their lifetime, suggesting that the genetic predisposition can be antagonized by resistant factors. BRCA1+ was inherited from an ancestor of the carrier family thousand years ago. We hypothesize that evolution could select certain genetic components to suppress oncogenesis caused by the predisposition. We compared germline variants in all genes in 27 pairs of breast cancer-unaffected and -affected BRCA1+ carriers, each pair inherited the same BRCA1+. We identified 12 deleterious variants enriched in breast cancer-unaffected carriers, all are common variants. A variant rs3735400 is located in ANLN, a cytokinesis-essential gene. Overexpression of variant-containing ANLN and suppressed expression of endogenous ANLN decrease ANLN nuclear localization and delay cell growth. Our findings suggest that common variants can be selected to resist oncogenesis imposed by BRCA1+.

  Study phs001243

• NIH Roadmap Epigenomics Program - Broad Institute

  For the NIH Roadmap Epigenomics project, we applied ChlP-Seq, HTBS and WGBS pipelines to generate comprehensive high-resolution maps of chromatin state and DNA methylation for 100 diverse cell types. Cell types were selected for their biological and medical importance, and for their potential to maximize the comprehensiveness of acquired epigenomic data. They include human ES cells, ES-derived cells, mesenchymal stem cells, reprogrammed stem cells and primary tissues. Comprehensive characterization of epigenetic marks ("the epigenome") is a critical step towards a global understanding of the human genome in health and disease. In this study we provide unprecedented views of the human epigenetic landscape and its variation across cell states, which offer fundamental insight into the functions and interrelationships of epigenetic marks, and provide a framework for future studies of normal and diseased epigenomes. The Roadmap Epigenomics Broad cohort is utilized in the following dbGaP sub-study. To view molecular data and derived variables collected in this sub-study, please click on the following sub-study below or in the "Sub-studies" box located on the right hand side of this top-level study page phs000700 the Roadmap Epigenomics Broad cohort. phs000610 RM_Epigenomics_Broad_Alz

  Study phs000700

• Next Generation Mendelian Genetics: Neonatal Diabetes

  The NHGRI Next Generation Mendelian Genetics project uses exome resequencing to identify variants in unsolved Mendelian diseases. Neonatal diabetes mellitus (ND) is a rare form of monogenic diabetes (90,000-260,000 live births) that is diagnosed in the first 6 months of life. The disease has been classified as transient or permanent and although it can be inherited, more frequently is sporadic as a result of 'de novo' mutations. Defects in 12 genes have been found as responsible for the disease (defects in the paternally imprinted chromosomal region 6q24, IPF1, SLCA2A, INS, EIF2AK3, GCK, FOXP3, GLIS3, PTF1A, HNF1Beta, KCNJ11 and ABCC8). The two subunits of the ATP-sensitive K channel (ABCC8 and KCNJ11) and the insulin gene (INS), account for almost half of the cases and similar to CHI, the other half, remains genetically unexplained. We became part of this study when we submitted 4 DNA samples for exome sequencing, from patients with NDM of Caucasian ancestry, which had no mutations identified in ABCC8 or KCNJ1, with the goal to identify new mutations in known genes or new mutations or genetic variants in new genes.

  Study phs000542

• Youth Drug Abuse, ADHD and Related Disorders

  There are two major aims with this study. 1. To describe the developmental trajectory of (a) a community-based sample of youth with a childhood diagnosis of ADHD that has been prospectively followed from childhood into adulthood (approximately a 17-year span), and (b) a clinical sample of youth that received drug abuse treatment during adolescence (variable time span). 2. To examine the association of phenotypes of drug involvement severity and risk alleles that prior research has suggested to be associated with drug abuse and externalizing disorders. The sample (N=607) consists of three groups based on youth status: Treatment, High Risk, and Control. These groups are defined as follows: Treatment - attended treatment or a brief intervention for a substance use disorder during adolescence (n=402); High Risk - elevated scores on standardized measures of disruptive behaviors during childhood based on teacher and parent reports (n=142); Control - normative scores during childhood on standardized measures of disruptive behaviors based on teacher and parent reports, and absent of any DSM-based behavioral/mental disorder when assessed during childhood based on parent report (n=66). Among the 610 participants who provided DNA, 607 are usable samples.

  Study phs001734