3906 results for "*geneti*"

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• Genetics and Functional Studies of Autosomal Recessive Neurological Disorders

  Neurological conditions account for over 6% of the global disease burden. There are more than 600 neurological disorders, and cognitive dysfunction, also referred to as intellectual disability (ID), occupies a prominent position in this list. Cognitive dysfunction arises from the failure of neuronal cells to organize into a complex network and remodel this network in response to learning and experience. It is manifested by deficits in adaptive behaviors in everyday social and practical skills. Due to its high prevalence and the lifetime cost of care per individual, in the range of $1-2 million in United Sates (CDC), it presents a significant health burden. Genetic and functional studies of the genes and protein determinants of ID have helped to elucidate the molecular pathways of human brain development in health and disease. However, the identity of a large number of essential molecular and cellular components still remain elusive. The objectives of our study are to expand the genetic repertoire of causal ID genes and characterize their role in neuronal structure and cognitive function. The rationale is that identification and functional elucidation of causative gene variants that lead to cognitive dysfunction will be essential for understanding brain function and for developing improved diagnostic tools and efficacious preventive and therapeutic agents for neurological disorders, including ID. There are 3 aims of our comprehensive research program: 1) Ascertain and clinically phenotype members of extended families segregating autosomal recessive intellectual disability (ARID); 2) identify new ARID genes and gene products; and 3) determine the functions of prioritized novel ARID genes using multifaceted approaches, including analysis of spatiotemporal expression patterns in mouse brain, targeting in cultured rat hippocampal neurons, effects on cell morphology and synapse abundance, synaptic transmission and plasticity in neuronal cells by electrophysiology and live-cell imaging assays. The project will advantageously combine human clinical assessment, genetic and functional analyses relevant to brain development and function. Impact: Execution of the proposed studies will generate new knowledge that is clinically relevant, with high potential to impact ID molecular diagnosis, prognoses, and identify novel therapeutic targets to slow progression, delay onset, and possibly devising precision medicine approaches for ID.

  Study phs003298

• Genetic Modifiers of Syndromic Orofacial Clefts

  Reduced penetrance and variable expressivity are common, but poorly understood, features of most monogenic diseases. Genetic modifiers are possible factors to contribute to this phenotypic variability and blur the traditional distinction between monogenic and complex disease. This study focuses on the most common orofacial cleft syndrome (Van der Woude syndrome, VWS) and nonsyndromic orofacial clefts (OFCs), which intersect both in phenotype and in genetic etiology, as a model to understand reduced penetrance and variable expressivity. VWS occurs in 1 in 35,000 individuals and accounts for 2% of all OFCs. The features of VWS include an OFC and/or lower lip pits, but 15% of VWS patients present with an isolated OFC, making them indistinguishable from nonsyndromic OFC patients. Mutations in the genes IRF6 or GRHL3 cause VWS, but approximately 20% of VWS patients currently lack a molecular diagnosis. Furthermore, there are few genotype-phenotype correlations for known mutations and patient phenotypes. By contrast, GWAS of nonsyndromic OFCs have identified a number of risk factors, some of which we have shown increase risk for specific types of OFCs or act as modifiers of OFC subtypes. Whole genome sequencing will be used to identify the remaining genetic mutations for VWS, determine the relationship between those genes/regions with nonsyndromic OFCs, and identify rare and common modifiers of VWS and OFC phenotypes. These analyses will provide further insight into the genetic architecture of VWS and OFCs and will serve as a model for exploring links between other Mendelian disorders that share phenotypes with complex traits.

  Study phs002221

• FinaleMe: Predicting DNA Methylation by the Fragmentation Patterns of Plasma Cell-Free DNA

  Analysis of DNA methylation in cell-free DNA (cfDNA) reveals clinically relevant biomarkers but requires specialized protocols and sufficient input material that limits its applicability. Millions of cfDNA samples have been profiled by genomic sequencing. To maximize the gene regulation information from existing datasets, we developed FinaleMe, a non-homogeneous Hidden Markov Model (HMM), to predict DNA methylation of cfDNA and, therefore, tissues of origin directly from plasma whole genome sequencing (WGS). We validated the performance with 80 pairs of deep and shallow coverage WGS and whole genome bisulfite sequencing (WGBS) data from both cancer patients and healthy controls.

  Study phs003287

• Breast Cancer in Blacks: Impact of Genomics, Healthcare Use and Lifestyle on Outcomes (BRIGHT)

  Young Black females bear a disproportionate burden of breast cancer (BC) mortality compared to White females and are underrepresented in clinical studies. It remains critical to understand factors that contribute to the high mortality from BC among young Black females in order to improve outcomes. The higher BC mortality rate among young Black females with breast cancer is partially attributed to the disproportionately higher proportions who develop the aggressive triple-negative breast cancer (TNBC). In addition to biologic factors, timely access to care, and lifestyle factors contribute to this disparity. Consequently, we sought to evaluate the interplay between biologic and non-biologic contributors to BC outcomes (i.e., BC disease-free survival (DFS)), and to better characterize the highly aggressive TNBC among young Black females based on distinct molecular subtypes. Ultimately, it is critical to assess both biologic and non-biologic factors to fully understand and address existing health disparities in this population. Through prior and subsequent recruitment of a population-based study of young Black females diagnosed with invasive breast cancer spanning 2009-2016, we: 1) assessed the contribution of biologic and non-biologic factors on BC-DFS observed among young Black females with BC, and 2) investigated molecular features of the subgroup with TNBC. Through this study, consented participants were asked to provide a saliva sample from which DNA was extracted for germline analyses, including germline inherited cancer genetic testing and Infinium Expanded Multi-Ethnic Genotyping Array. Breast cancer tumor specimens were also collected, and tumor RNA was extracted from viable FFPE tumor samples. Tumor RNA analyses included gene expression profiling through NanoString PAM50.Data that will be available through dbGaP for this study include SNP array data and PAM50 data.

  Study phs003466

• Whole Genome Sequencing of Bilateral Cleft Lip and Palate Families from Africa: CIDR

  The focus of this study is to identify and test both common and rare genetic variants that elevate risk for CL/P, and to identify genetic variants associated with specific orofacial cleft (OFC) phenotypes in the population that has accumulated the greatest genetic variation in the human race. We hypothesize that bilateral complete cleft lip and palate (BCLP), the most clinically severe form of OFC, is associated with a higher mutation load than less severe forms (cleft lip only and unilateral cleft lip and palate) and focusing on BCLP will facilitate the discovery of novel risk variants.

  Study phs002623

• Kids First: The Genomic Basis of Structural Birth Defects Associated with Chromosome 18 Copy Number Changes

  Chromosome abnormalities are a common cause of structural birth defects. Both childhood cancers and structural birth defects are critical and costly conditions associated with substantial morbidity and mortality. Elucidating the underlying genetic etiology of these diseases has the potential to profoundly improve preventative measures, diagnostics, and therapeutic interventions.However, because these genomic copy number changes involve multiple genes and because most of these conditions are individually rare, defining the specific causative genes behind specific phenotypes has been a challenge. We met that challenge by spending the last 28 years enrolling and evaluating anyone with a chromosome 18 abnormality. The cohort now includes over 700 individuals with a wide variety of chromosome 18 copy number changes (CNV), as well as their parents. Because the vast majority of these participants have individually unique CNVs, we have been able to perform extensive genotype-phenotype correlations resulting in 58 publications. Of the 263 genes on chromosome 18, 28 are linked to specific hemizygous phenotypes. However, most have low penetrance. Genomic sequence data could identify variants in the extant allele that are hypermorphic and compensate for hemizygosity, or are hypomorphic and exacerbate hemizygosity. Additionally, there are phenotypes within this cohort that are rare, or an extreme version of one of the more common phenotypes. Genomic sequence data could help discover new biallelic conditions by revealing functional sequence variants of the extant allele. In both of these cases, there could also be variants in other genes on other chromosomes that may be associated with the phenotype that confer susceptibility or resilience. Inclusion of this unique cohort in the Gabriella Miller Kids First Pediatric Research Program can advance the goals of the program in several ways. First, by adding known susceptibility loci to the existing Kids First cohorts for the structural birth defects that are also found in our cohort. Second, for those structural birth defects known to be polygenetic, this cohort has a single defined risk factor which can simplify the search for secondary factors. Third, these studies can also bring clarity to people with chromosome 18 conditions and help to make the genotype more accurately predict phenotype. This approach could be a model for understanding the many other rare chromosome abnormalities which collectively are a common cause of structural birth defects.

  Study phs002627

• Extrachromosomal DNA Amplification Contributes to Small Cell Lung Cancer Heterogeneity and is Associated with Worse Outcomes

  Small-cell lung cancer (SCLC) is a very aggressive neuroendocrine lung cancer often associated with oncogenic MYC amplifications, which are known to drive SCLC heterogeneity marked by neuroendocrine (NE) and non-neuroendocrine (non-NE) cell states. The genetic mechanisms of MYC amplification and phenotypic plasticity between cell states is not known. Using data from cell-lines and a few patient-derived samples along with integrated whole-genome sequencing, long-range optical mapping, single-cell DNA sequencing, and fluorescence in situ hybridization, we have attempted to successfully characterize extrachromosomal DNA (ecDNA) as the primary source of MYC amplifications and driver fusions in SCLC.

  Study phs003190

• Experimental and Clinical Studies of Presbycusis

  This study aimed to investigate genes and variants associated with adult-onset progressive hearing loss, a common and complex disease with a strong genetic component.Participants enrolled in an ongoing longitudinal study of age-related hearing loss at the Medical University of South Carolina (MUSC), dating from 1987. Pure tone thresholds at 0.25, 0.5, 1.0, 2.0, 3.0, 4.0, 6.0 and 8.0 kHz were obtained for each ear of each person, along with questionnaire responses concerning noise exposure history. Based on the audiometry, participants were classified into 5 groups as "Older-Normal", "Metabolic", "Sensory", "Unclassified" and "Unselected" by their hearing loss.Exome sequencing was carried out using the Agilent SureSelect X2 Target Enrichment System (version 5) and the Agilent SureSelect Human All Exon V5 kit, which included 5' and 3' UTRs. DNA was sheared using the Covaris S220 focused ultrasonicator. Libraries were sequenced on the Illumina HiSeq 2500. Variant loads per gene were calculated and compared between groups. Individual variants affecting hearing thresholds were also identified. Analyses were followed up in a second cohort. Several genes and variants were identified as novel candidates associated with both better and worse hearing. Data available through dbGaP include whole exome sequencing (WES) files and audiometric phenotyping.

  Study phs003327

• Epigenetic Changes in Immune Response and Oncogenesis Related Genes Caused by Heavy Metal Long-Term Exposure

  Our study investigated methylation changes in CpG islands located in immune response and oncogenesis related genes in humans induced by long-term environmental heavy metal exposure. We assessed the methylation levels of 654 CpG sites located on NFKB1, CDKN2A, ESR1, APOA5 and IGF2/H19 genes by targeted bisulfite sequencing (target enrichment by 48.48 Access Array Integrated Fluidic Circuit (Fluidigm, USA) in a cohort of 40 subjects living near a metal mining area (the Kapan mining region, Armenia) and 40 unexposed subjects. We performed linear regression on our data to find differentially methylated positions with adjustment for gender, age, BMI class, smoking, and plasma concentrations of 21 essential and non-essential metals detected by ICP-MS. Our study showed hypomethylation of five CpG sites in the NFKB1 promoter region in the exposed group. According to our findings, the methylation changes of CpG sites in NFKB1, CDKN2A, IGF2 and ESR1 genes are associated with multiple and specific metal exposures. Targeted bisulfite sequencing data obtained for 80 subjects who participated in this study are available through dbGaP. The tables contain information about age, sex, BMI, smoking and exposure status, as well as race and ethnicity of the study participants.

  Study phs003392

• PIEZO1 Loss of Function Compound Heterozygous Mutation in the Rare Congenital Human Disorder Prune Belly Syndrome

  Prune Belly Syndrome (PBS) is a rare congenital myopathy that is incompletely understood genetically. In this IRB approved study, one white Non-Hispanic 35 year-old male PBS proband was prospectively enrolled and phenotyped. Blood lymphocyte DNA from the proband underwent paired-end Whole Exome Sequencing using the Illumina SureSelect kit and HiSeq2500 sequencer with data pipeline analysis. We aligned the subject's sequence against the GRCh38/hg19 assembly and variant calling was performed using data training sets from the 1000 Genomes Project, Omni 2.5 M SNP microarray, and HapMap phase 3.3. These variants were filtered for rare minor allele frequency ( 0.9, CADD score > 20, GERP > 4, MutationTaster = “DC”, Mutation Assessor = “M” or “NE”, and Vest > 3.00. Rare and novel candidate functional variants were screened in the ClinVar database for prior association with smooth muscle myopathy (SMM). Only variants that met these criteria were included for further analysis. Confirmed variants had inheritance analysis performed on available samples. Our WES analysis identified novel compound heterozygous variants in the PIEZO1 gene. We conducted an extensive functional analysis of the PIEZO1 PBS variants that revealed loss-of-function characteristics. Thus, PIEZO1 mutations may be causal for PBS. Our WES data will be available through dbGaP.

  Study phs003475

• Enhancing Open Data Sharing for Functional Genomics Experiments: Measures to Quantify Genomic Information Leakage and File Formats for Privacy Preservation

  This study was designed to develop methods that address the privacy risk associated with genetic variants obtained from genomic sequencing experiments. The preponderance of readily available genetic sequencing experiments has enabled the generation of datasets whose target purposes range from the genotyping of individuals for medical and forensic analyses, to the acquisition of molecular information for biological model development. However, by virtue of the experimental procedure, the raw sequences are tagged with small bits of patients' private variant information. In addition, depending on the protocol, these experiments may identify sequences from exogenous species. Raw human and microbial sequences can be analyzed as a whole to learn both general facts about biology, but can also be used to determine sensitive information about an individual. This presents a privacy conundrum for data sharing.To address privacy concerns, we have developed several mathematical and computational approaches to quantify the risk of disclosure of sensitive information from genetic sequence data, and to sanitize the associated reads in a manner that optimally maintains the utility of the data. In addition, we have generated environmental samples containing genetic information from consented individuals to evaluate the risk posed by such data. These samples were then used to assess the efficacy of the computational methods. Human-derived and -associated samples that are damaged or obscured by environmental factors represent the scope of samples used for experimentation in this study. Samples include, but were not limited to, swabs of contacted objects and glass slides coated in saliva from consented individuals. Blood samples were also acquired from the same consented individuals to create gold-standard comparison datasets.

  Study phs003166

• Diabetes Multi-Omic Investigation of Drug Response (DIAMOND)

  The Diabetes Multi-omic Investigation of Drug Response (DIAMOND) cohort is a population-based cohort of individuals with type-2 diabetes (T2D) who receive their care through a large health system serving southeast Michigan and metropolitan Detroit. The cohort represents the diversity of the population from which it was created. Because of their health plan membership, participants have a rich dataset of longitudinal clinical health information related to their care. The intent of the DIAMOND study is to use genomic profiling, drug exposure information, and electronic health record (EHR) derived outcome data to identify genetic predictors of treatment response. Genome-wide genotyping was performed using the AxiomTM Precision Medicine Research Array (ThermoFisher Scientific Inc.).

  Study phs003350

• Multi-Ethnic Study of Atherosclerosis (BioLINCC)

  The Multi-Ethnic Study of Atherosclerosis (MESA) is a study of the characteristics of subclinical cardiovascular disease (disease detected non-invasively before it has produced clinical signs and symptoms) and the risk factors that predict progression to clinically overt cardiovascular disease or progression of the subclinical disease. MESA researchers study a diverse, population-based sample of 6,814 asymptomatic men and women aged 45-84. Thirty-eight percent of the recruited participants are white, 28 percent African-American, 22 percent Hispanic, and 12 percent Asian, predominantly of Chinese descent. Data available for request include phenotypic data previously released on BioLINCC as well as raw images (E.g. Echocardiogram) and raw tracing data files (e.g. Electrocardiogram). These new data are intended to be made available to interested researchers via BioData Catalyst, will include participants irrespective of participation in genetics (i.e. the full MESA cohort), and may be merged with currently posted (to dbGaP) phenotype and molecular datasets (WGS, GWA, RNA Seq, Methylation, Metabolomics, and Proteomics).

  Study phs003288

• Exploring the Genomic Dark Matter of Neurodevelopmental Disorders

  Neurodevelopmental Disorders (NDDs) are a group of disorders that typically manifest early in development and may give rise to impaired cognition, communication, adaptive behavior, and psychomotor skills. This study aims to take a more comprehensive view into the genomic landscape of structural variants implicated in NDDs with intellectual disability (ID). We have evaluated the genome of families with a genetically unsolved severe NDD via optical genome mapping. This study identified likely pathogenic or pathogenic structural variants in known NDD genes, including BCL11A, OPHN1, PHF8, SON, and NFIA. Data is available in VCF format, following the standard filtering settings in Bionano Access and available as "variants_combine_filters_inMoleRefine1.vcf" files.

  Study phs002937

• Cell Type-Specific and Disease-Associated eQTL in the Human Lung

  This study was conducted to investigate the genetic control of gene expression in a cell-type and context-specific manner in the human lung. We performed single-cell RNA-sequencing (scRNA-seq) of lung tissue from 66 Interstitial Lung Disease (ILD) cases and 48 unaffected donors. Employing a pseudo-bulk approach, we mapped expression quantitative trait loci (eQTL) across 38 cell types. The scRNA-seq data presented here include previously published (PMID 34262047) and unpublished samples. ILD tissue samples were obtained from lungs removed at the time of lung transplantation at either Vanderbilt University Medical Center (VUMC) or the Norton Thoracic Institute (NTI). Control tissue samples were obtained from lungs declined for organ donation either at the Donor Network of Arizona (DNA) or VUMC. The self-reported ethnicities of donors were 66.7% European, 9.6% African American, 17.5% not available (N/A), and 6.1% other. The smoking history includes 46.5% ever smoker, 29.8% never smoker, 23.7% N/A. For genotyping, flash-frozen tissue in DNA/RNA shield was homogenized via a bullet blender. Genomic DNA was extracted using Zymo Quick DNA/RNA microprep plus kit. Library preparation and low-pass Whole Genome Sequencing (WGS) were carried out at TGen or by Gencove Inc. At TGen, libraries were prepared using PCR-free Watchmaker kits (Watchmaker Genomics) with 200 ng input. Genomes were sequenced on NovaSeq at low coverage (typically 0.4–1x). The resulting sequence data were processed and imputed using Gencove's imputation platform.

  Study phs003521

• Molecular Characterization of Hemimegalencephaly

  Somatic mutations, in which a fraction of the cells in the body have a deleterious mutation, are well recognized in cancer but only recently appreciated in neurological disease. Given a somatic mutation in a population of progenitor cells, all daughter cells inherit the mutation and are able to express the resultant phenotype as a function of the differentiation program. We recently identified the first de novo somatic mutations in the developing brain in the condition hemimegalencephaly (HME), a catastrophic focal epilepsy condition associated with a malformation of cerebral cortical development (MCD). HME is one of the most severe MCD syndromes, characterized by massive hamartomatous overgrowth of either of the two cerebral hemispheres. Cerebral hemispherectomy is a frequent treatment for refractory epilepsy, allowing the sampling of diseased tissue. By comparing DNA from a diseased brain with DNA from blood/saliva, we identified de novo somatic mutations in PIK3CA, AKT3 or MTOR, part of the mTOR pathway. Mutations were present in 8-40% of sequenced alleles in various brain regions sampled during surgery and in some codons known to activate proteins.• Population informationPatient samples were collected from multiple centers. The population is Caucasian and Hispanic• Molecular technologies employedWhole-exome sequencing• Principal findings of the studyWe were the first to describe mTOR-related and non-mTOR mutations causing hemimegalencephaly, and we described two-hit mutational models to explain the genetic pathogenesis of hemimegalencephaly

  Study phs002156

• Epigenetic Landscape of Human Parathyroids

  The goal of this study is to produce a comprehensive map of the chromatin landscape of human parathyroids. Data from 20 subjects with parathyroid adenoma causing primary hyperparathyroidism were used. For the sequencing platform, Illumina HiSeq 2000 with V3 high-output kits were used. For the data processing pipeline, reads were aligned to hg19 using Bowtie or BWA. For RNA-seq data, transcript levels were estimated per gene to RPKM using Cufflink. For ChIP-seq and ATAC-seq data, enrichment peaks were estimated compared to inputs or background using MACS2 after merging reads from replicates. For DNase-seq, significant peaks compared to background distribution were computed using Hotspot. For Hi-C data, significant interactions were detected using Juicer HiCCUPS and 5 kb resolution for the merged data from replicates. Chromatin states for parathyroids were computed using ChromHMM based on ChIP-seq profiles in parathyroids of H3K4me3, H3K4me1, H3K27ac, H3K36me3, H3K27me3 and H3K9me3 and the emission matrix from 18 states pre-trained in the Roadmap Epigenomics. Gene expression, binding positions of transcription factor, open chromatin regions, 3D-chromatin interaction, and chromatin states are submitted.

  Study phs003302

• Transcriptomic and Epigenetic Profiling of SCLC Patient Samples

  Small cell lung cancer (SCLC) is an aggressive disease with poor outcomes and limited treatment options. Recent studies have identified transcriptionally defined subsets of SCLC that may allow for the personalization of treatment. Here we use transcriptomic sequencing and methylation profiling (RRBS) of biopsy and cfDNA to develop a highly accurate DNA methylation-based classifier to distinguish SCLC subtypes. These results demonstrate the clinical feasibility of molecular subtyping of SCLC.

  Study phs003416

• Postmortem Analysis of the Caudate Nucleus in Schizophrenia

  This postmortem study examines genomic signatures (gene, transcript, exon, and exon-exon junction) in the caudate nucleus of individuals with or without psychiatric illnesses. We characterized genetic and epigenetic changes across the lifespan of 443 donor subjects, including 245 individuals without psychiatric illness, 154 individuals with schizophrenia, and 44 individuals with bipolar disorder. The subjects are 210 from African and 233 from European ancestries. Combining expression quantitative trait loci (eQTL) analysis, Mendelian randomization with the latest schizophrenia genome-wide association study (GWAS), transcriptome-wide association study (TWAS) and differential expression analysis, we identified many genes associated with schizophrenia risk, including potentially the dopamine D2 receptor short isoform. We found that antipsychotic medication has an extensive influence on caudate gene expression. We constructed caudate nucleus gene expression networks that highlight interactions involving schizophrenia risk. These analyses provide a resource for the study of schizophrenia and insights into risk mechanisms and potential therapeutic targets. There are 120 subjects in this study which are also present in the study phs000417.

  Study phs003495

• Genetic Causes of Congenital Anosmia

  The Genetic Causes of Congenital Anosmia study was designed to provide a list of candidate genes that are potentially causal for isolated congenital anosmia (ICA), a rare inherited disorder where individuals lack a sense of smell from birth in the absence of a known genetic syndrome (i.e. Kallman's syndrome). This study includes 193 participants from 18-87 years of age, divided into two cohorts: family and non-family. Genetic data from the family cohort was analyzed in a case-control family design to generate a list of 162 candidate genes for ICA. A targeted search for variants in this list of genes was then conducted in the non-family cohort to create a prioritized list of genes for further study. Ten unrelated families were recruited for the family cohort for a total of 52 participants, 25 of which had anosmia. The non-family cohort consisted of 141 anosmic individuals. 3 additional normosmic participants from incomplete families were collected, one of whom has a participating family member in the non-family cohort, and so has data provided here. Data collection was conducted remotely, resulting in 146 participants recruited from the United States, and 48 recruited internationally from ten different countries. Participants were interviewed for their anosmia status and to confirm that they had no known genetic syndromes. Participants also completed the University of Pennsylvania Brief Smell Identification Test (BSIT; Doty et al., 1984) to confirm their anosmic/normosmic status and provided a saliva sample for whole exome sequencing (WES). Participants who had family members with anosmia provided pedigree information via interview. Data submitted to dbGap include whole exome sequences from 194 individuals (163 anosmic) conducted with Illumina HiSeq2500 and Illumina NovaSeq next generation sequencing technologies. Family pedigree information for the 10 participating families and all participants in the non-family cohort who have non-participating anosmic family members was also included. Our goal was to provide a resource for further research into the genetics of isolated congenital anosmia and to aide in the understanding of this disorder, as well as human olfaction, in general. The WES data provided could be further analyzed for polygenic interactions, additional non-targeted analysis on the non-family cohort, or combined into databases of other anosmic populations for further gene targeting or selection.

  Study phs003328

• BarcUVa-Seq (Biology of Colorectal Cancer Risk Enhancers)

  This study was designed to generate a cohort of normal colon mucosal biopsies from the "average risk" population. Its primary aims included the development of an RNA-seq dataset of normal colon mucosal biopsies across three colon regions (ascending, transverse and descending). Further, we aimed to provide plausible prioritization to genetic components of colorectal cancer risk by employing methods such as expression quantitative trait loci analysis. In doing so, we provide a novel reference dataset for the study of colon cancer risk in the healthy colon epithelium. RNA-seq was performed in batches on an Illumina HiSeq 2500 (batch 1-7) or NovaSeq 6000 (batch 8) on a total of 463 samples. Matched genotyping data was generated on the Illumina OncoArray BeadChip. Phasing was carried out using Minimac 3 and imputation was performed using The Haplotype Reference Consortium panel on the Michigan Imputation Server.Genotype and RNA-seq data will be made available in dbGaP.

  Study phs003338

• NHLBI TOPMed - NHGRI CCDG: The GENetics in Atrial Fibrillation (GENAF) Study

  The Genetics in AF (GENAF) study enrolled individuals with early-onset lone AF before age 50 in Norway between 2009 and 2016. Early-onset was defined as diagnosis of AF before age 50. Lone AF was defined as AF in the absence of clinical or echocardiographic findings of cardiovascular disease, hypertension, metabolic or pulmonary disease. AF was documented in ECG. All participants underwent clinical examination, including ECG, echocardiography, and blood draw, from which DNA has been extracted. The study conforms to the principles of the Declaration of Helsinki and was approved by the Regional Ethics Committee (REK) in Norway (Protocol reference number: 2009/2224-5). All included patients gave written informed consent.

  Study phs001547

• Single Duplex DNA Sequencing with CODEC Detects Mutations with High Sensitivity

  Detecting mutations from single DNA molecules is crucial in many fields but challenging. Next generation sequencing (NGS) affords tremendous throughput but cannot directly sequence double-stranded DNA molecules (single duplexes) to discern the true mutations on both strands. Here, we present Concatenating Original Duplex for Error Correction (CODEC) which confers single duplex resolution to NGS. CODEC affords 1,000-fold higher accuracy than NGS, using up to 100-fold fewer reads than Duplex Sequencing. CODEC revealed mutation frequencies of 2.72 x 10-8 in sperm of a 39-year-old individual, and somatic mutations acquired with age in blood cells. CODEC detected genome-wide clonal hematopoiesis mutations from single DNA molecules, single mutated duplexes from tumor genomes and liquid biopsies, microsatellite instability (MSI) with 10-fold greater sensitivity, and mutational signatures and specific tumor mutations with up to 100-fold fewer reads. CODEC enables more precise genetic testing and reveals biologically significant mutations which are commonly obscured by NGS errors. We applied CODEC to clinical colon and breast neoplasm samples and uncovered expected mutational signatures including homologous recombination deficiency (HRD) and MSI.

  Study phs003255

• Single Cell Genotypic and Phenotypic Analysis of Measurable Residual Disease in Acute Myeloid Leukemia

  Acute myeloid leukemia (AML) is a group of blood cancers with high mortality. Even though complete remission is often achieved, majority of the AML patients still relapse. Measurable residual disease (MRD), defined as the population of cancer cells which persists following chemotherapy, is responsible for AML relapse. Understanding the biology enabling MRD clones to resist therapy is necessary to guide the development of curative treatments more effectively. Discriminating residual leukemic clones, preleukemic clones, and normal precursors remains a challenge with current MRD tools. We developed a single cell MRD (scMRD) assay by combining flow cytometric enrichment of the targeted precursor/blast population with integrated single cell DNA sequencing (scDNA-seq) and immunophenotyping (Tapestri, Missionbio). The platform utilizes a custom amplicon panel covering 109 amplicons across 31 genes frequently mutated in AML and a panel of 42 oligo-conjugated antibodies against surface makers. We applied our scMRD assay to sequence 30 MRD samples (multiplexed into 6) from 29 AML patients to study the clonal architecture and protein correlation. In addition, 2 MRD samples were sequenced with scDNA+protein sequencing technology without enrichment or multiplexing. Five patients with AML at diagnosis were also sequenced with scDNA+protein sequencing technology without enrichment or multiplexing. In order to establish the sensitivity of our scMRD assay, we spiked AML cells into normal bone marrow cells. We sequenced 12 such spiked samples after multiplexing.

  Study phs003233

• Deterministic Evolution and Stringent Selection During Pre-Neoplasia

  The earliest events during human tumor initiation are poorly characterized but may hold clues as to how to detect and prevent malignancy. Here we model this occult process by engineering TP53 deficiency in primary human gastric organoids and performing experimental evolution in multiple clonally derived cultures over two years, thereby defining causal relationships between this common initiating genetic lesion and resulting phenotypes. TP53 loss induced progressive aneuploidy, including copy number alterations and complex structural variants that are common in established gastric cancers, and which accrued along a defined temporal order. Longitudinal single cell sequencing of TP53 deficient gastric organoids similarly indicates progression towards malignant transcriptional programs. Moreover, lineage tracing with expressed cellular barcodes revealed highly reproducible dynamics whereby initially rare subclones with shared transcriptional programs repeatedly attain clonal dominance. This powerful platform for experimental evolution reveals stringent selection and convergence at the genotypic and phenotypic levels in pre-malignant epithelial organoids, illuminating evolutionary constraints and barriers to malignant transformation.

  Study phs003249