12521 results for ""non-traditional+communal+storytelling+approach"+novel+segment+noted+in+critical+commentary"

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• Origination of Ovarian Cancer is Dependent on Specific Aneuploidy Landscape

  Ovarian high-grade serous carcinoma (HGSC), a highly chromosomally instable malignancy, develops through sequential stages of precursors in fallopian tubes including histologically unremarkable but TP53 mutated clones (p53 signature) and serous tubal intraepithelial carcinoma (STIC). Here, we applied RealSeqS to assess aneuploidy in 127 microdissected tubal regions. We found nearly all p53 signatures lost the entire Chr17 chromosome, offering a “two-hit” mechanism of both TP53 and BRCA1 in BRCA1 germline mutation carriers. Proliferatively active STICs harbor gains of 19q12 (CCNE1), 19q13.2, 8q24 (MYCyc), or 8q arm, while proliferatively dormant STICs show 22q loss. Based on aneuploidy patterns in a training set (n= 67), we developed an algorithm, REAL-FAST, to classify NFTE and STICs into 5 clusters. In an independent validation set (n= 72), REAL-FAST was able to detect STIC/HGSC with high sensitivity and specificity. Taken together, REAL-FAST promises a molecular test for diagnosing HGSC precursor lesions based on specific aneuploidy patterns.

  Study EGAS00001007220

• Colon cancer targeted sequencing study contaning WBCs, primary tumor tissue and plasma samples

  In the setting of localized colon cancer (CC), circulating tumor DNA (ctDNA) monitoring in plasma has shown potential for detecting minimal residual disease (MRD) and predicting higher risk of recurrence. With the tumor-only sequencing approach, however, germline variants may be misidentified as somatic variations, precluding the possibility of tracking in up to 11% of patients due to a lack of known somatic mutations. In this study comprising 148 prospectively recruited localized CC patients, a custom 29-gene panel was utilized to sequence both tumor tissue and matched white blood cells (WBCs) to enhance the accuracy of sequencing results. Performing targeted sequencing of paired tumor tissue and WBCs samples detected additional somatic mutations and increased the number of patients eligible for MRD tracking in plasma, although MRD detection sensitivity was not increased. Furthermore, the germline testing approach revealed the presence of pathogenic germline variants, thereby helping identify patients at elevated risk of hereditary cancer syndromes.

  Study EGAS50000000059

• Mechanisms of Extreme Genomic Instability at Large Transcribed Genes

  Inhibiting DNA replication leads to copy number variant (CNV) formation throughout the genome, especially at chromosome fragile sites (CFSs). We previously showed that these hotspots for genome instability reside in late-replicating domains associated with large transcribed genes. In this study, we compared aphidicolin (APH)-induced CNV and CFS frequency between wild-type cells and isogenic cells in which FHIT gene transcription was ablated. We further examined the impact of altering RNase H1 expression on CNV or CFS induction frequency and analyzed R-loop formation genome-wide in a human fibroblast cell line. Data sets include Bru-seq nascent RNA transcription, whole genome sequencing for replication timing, SNP microarray analysis, and DRIP-seq. Results suggest that large gene transcription is a determining factor in replication stress-induced genomic instability and that CFSs mainly result from transcription-dependent passage of unreplicated DNA into mitosis with low R-loop levels observed at these loci.

  Study phs002066

• Genetic Effects on Gene Expression and Splicing during Human Neurogenesis

  Interpretation of the function of non-coding risk loci for neuropsychiatric disorders and brain-relevant traits via gene expression and alternative splicing quantitative trait locus (e/sQTL) analyses is generally performed in bulk post-mortem adult tissue. However, genetic risk loci are enriched in regulatory elements active during neocortical differentiation, and regulatory effects of risk variants may be masked by heterogeneity in bulk tissue. Here, we map e/sQTLs, and allele-specific expression in cultured cells representing two major developmental stages, primary human neural progenitors (n=85) and their sorted neuronal progeny (n=74), identifying numerous loci not detected in either bulk developing cortical wall or adult cortex. Using colocalization and genetic imputation via transcriptome-wide association, we uncover cell-type specific regulatory mechanisms underlying risk for brain-relevant traits that are active during neocortical differentiation. Specifically, we identified a progenitor-specific eQTL for CENPW co-localized with common variant associations for cortical surface area and educational attainment.

  Study phs002493

• Cell-Type Specific Effects of Genetic Variation on Chromatin Accessibility During Human Neuronal Differentiation

  Common genetic risk for neuropsychiatric disorders is enriched in regulatory elements active during cortical neurogenesis. However, the mechanisms mediating the effects of genetic variants on gene regulation are poorly understood. To determine the functional impact of common genetic variation on the non-coding genome longitudinally during human cortical development, we performed a chromatin accessibility quantitative trait loci (caQTL) analysis in neural progenitor cells and their differentiated neuronal progeny from 92 donors. We identified significant genetic effects on 988/1,839 neuron/progenitor regulatory elements, with highly cell-type and temporally specific effects. A subset (~30%) of caQTLs were also associated with changes in gene expression. Motif-disrupting alleles of transcriptional activators generally led to decreases in chromatin accessibility, whereas motif-disrupting alleles of repressors led to increases in chromatin accessibility. By integrating cell-type specific caQTLs and brain-relevant genome-wide association data, we were able to fine-map and identify regulatory mechanisms underlying non-coding neuropsychiatric disorder risk loci.

  Study phs001958

• Genome-wide Identification of Variants Affecting Early Human Brain Development

  This is a genome-wide association study (GWAS) of global brain tissue volumes in human infants. The published study for this project includes 561 infants, and 239 parents gave consent for data sharing through dbGaP. An intronic single-nucleotide polymorphism (SNP) in IGFBP7 (rs114518130; GeneID: 3490) met genome-wide significance for gray matter volume (P=4.15x10-10). An intronic SNP in WWOX (rs10514437; GeneID: 51741) neared genome-wide significance for white matter volume (P=1.56x10-8). Additional loci with small P-values include psychiatric GWAS associations and transcription factors expressed in the developing brain. Genetic risk scores for schizophrenia and ASD, and the number of genes affected by rare copy number variants (CNV burden) did not predict global brain tissue volumes. Integrating these results with large-scale GWAS in adolescents [Philadelphia Neurodevelopmental Cohort (PNC)] and adults [Enhancing Neuro Imaging Genetics through Meta-Analysis version 2 (ENIGMA2)] suggested minimal overlap between common variants impacting brain volumes at different ages.

  Study phs001122

• Single-Cell Analysis of Human Adipogenesis

  The data in this study consists of RNA sequencing reads and read counts from single-cell and single-nuclei RNA sequencing experiments performed on two cell lines to investigate the transcriptional landscape of human adipogenesis in both the brown and white adipose tissue lineage. The two cell lines are human preadipocytes collected and isolated from a defined anatomical location in the neck of a single individual. This depot is known to harbor white adipose tissue (WAT) and brown adipose tissue (BAT). These white and brown preadipocytes were immortalized for the purposes of studying human adipogenesis in vitro. In this study we induced differentiation of these two preadipocyte lines and performed RNA sequencing on over 135,000 single cells spanning a 20-day time course from unperturbed preadipocytes to mature adipocytes from both brown and white lineages. Additionally, we performed both single-cell and single-nuclei RNA sequencing to comprehensively compare the advantages and disadvantages of either technique.

  Study phs002461

• A Whole Genome Association Scan for Myopia and Glaucoma Endophenotypes using Twin Studies

  Myopia and glaucoma are highly prevalent ophthalmic disorders worldwide and contribute significantly to ocular morbidity. There is substantial evidence that genetic factors play a significant role in the development of non-syndromic myopia and glaucoma. We propose to perform mapping studies for well-characterized twin populations in the United Kingdom and Australia in order to ultimately identify implicated genes for these disorders and related ocular parameters. This will provide a fundamental molecular understanding of how these disorders develop, and may lead to directed physiologic (i.e. pharmacologic, gene therapy) interventions. Our aim is to dissect the genetic basis of the eye disorders myopia and glaucoma. Instead of limited analyses of the trait/disease in a dichotomous manner, we are using continuous phenotypes of measures of refraction and intermediate phenotypes of glaucoma to analyze quantitative traits in unselected population samples of volunteer twins. Achievement of this goal requires cooperative efforts and large sample sizes. Thus, we have created an international collaboration of large complementary studies.

  Study phs000142

• Sézary Syndrome Originates from Heavily Mutated Hematopoietic Progenitors

  The pathogenesis of cutaneous T cell lymphoma (CTCL) remains unclear. To study the malignant transformation of CTCL, we collected matched hematopoietic stem cell (HSC) extracts from bone marrow, CD4+CD26- malignant T cells, CD4+CD26+ normal T cells, and CD34+ HSCs from apheresis performed on 4 patients. To establish the baseline for calling true mutations without using hematopoietic cells, we also cultured bone marrow fibroblasts from each patient to use as normal controls. Whole exome sequencing (WES) was performed on all samples for somatic mutation calling. We identified >200 mutations in CD34+ HSCs derived from either bone marrow or apheresis. Previously reported key oncodrivers in Sezary Syndrome were identified in autologous HSCs and malignant peripheral cells, but not in progenitor (bone marrow HSCs) cells. Also, we identified specific mutations shared by autologous HSCs and malignant peripheral cells in every patient. WES data of bone marrow HSCs, apheresis HSCs, CD4+CD26- T cells, CD4+CD26+ T cells, and fibroblasts will be available through dbGaP.

  Study phs003158

• Impact of Genetic Polymorphisms on Human Immune Cell Gene Expression

  While many genetic variants have been associated with risk for human diseases, how these variants affect gene expression in various cell types remains largely unknown. To address this gap, the DICE [Database of Immune Cell Expression, Expression quantitative trait loci (eQTLs) and Epigenomics] project was established. Considering all human immune cell types and conditions studied, we identified cis-eQTLs for a total of 12,254 unique genes, which represent 61% of all protein-coding genes expressed in these cell types. Strikingly, a large fraction (41%) of these genes showed a strong cis-association with genotype only in a single cell type. We also found that biological sex is associated with major differences in immune cell gene expression in a highly cell-specific manner. These datasets will help reveal the effects of disease risk-associated genetic polymorphisms on specific immune cell types, providing mechanistic insights into how they might influence pathogenesis.

  Study phs001703