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1.
Nature ; 604(7906): 509-516, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35396579

RESUMO

Rare coding variation has historically provided the most direct connections between gene function and disease pathogenesis. By meta-analysing the whole exomes of 24,248 schizophrenia cases and 97,322 controls, we implicate ultra-rare coding variants (URVs) in 10 genes as conferring substantial risk for schizophrenia (odds ratios of 3-50, P < 2.14 × 10-6) and 32 genes at a false discovery rate of <5%. These genes have the greatest expression in central nervous system neurons and have diverse molecular functions that include the formation, structure and function of the synapse. The associations of the NMDA (N-methyl-D-aspartate) receptor subunit GRIN2A and AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptor subunit GRIA3 provide support for dysfunction of the glutamatergic system as a mechanistic hypothesis in the pathogenesis of schizophrenia. We observe an overlap of rare variant risk among schizophrenia, autism spectrum disorders1, epilepsy and severe neurodevelopmental disorders2, although different mutation types are implicated in some shared genes. Most genes described here, however, are not implicated in neurodevelopment. We demonstrate that genes prioritized from common variant analyses of schizophrenia are enriched in rare variant risk3, suggesting that common and rare genetic risk factors converge at least partially on the same underlying pathogenic biological processes. Even after excluding significantly associated genes, schizophrenia cases still carry a substantial excess of URVs, which indicates that more risk genes await discovery using this approach.


Assuntos
Mutação , Transtornos do Neurodesenvolvimento , Esquizofrenia , Estudos de Casos e Controles , Exoma , Predisposição Genética para Doença/genética , Humanos , Transtornos do Neurodesenvolvimento/genética , Receptores de N-Metil-D-Aspartato/genética , Esquizofrenia/genética
2.
Nat Commun ; 13(1): 1632, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35347136

RESUMO

To identify genetic determinants of airway dysfunction, we performed a transcriptome-wide association study for asthma by combining RNA-seq data from the nasal airway epithelium of 681 children, with UK Biobank genetic association data. Our airway analysis identified 95 asthma genes, 58 of which were not identified by transcriptome-wide association analyses using other asthma-relevant tissues. Among these genes were MUC5AC, an airway mucin, and FOXA3, a transcriptional driver of mucus metaplasia. Muco-ciliary epithelial cultures from genotyped donors revealed that the MUC5AC risk variant increases MUC5AC protein secretion and mucus secretory cell frequency. Airway transcriptome-wide association analyses for mucus production and chronic cough also identified MUC5AC. These cis-expression variants were associated with trans effects on expression; the MUC5AC variant was associated with upregulation of non-inflammatory mucus secretory network genes, while the FOXA3 variant was associated with upregulation of type-2 inflammation-induced mucus-metaplasia pathway genes. Our results reveal genetic mechanisms of airway mucus pathobiology.


Assuntos
Asma , Transcriptoma , Asma/genética , Asma/metabolismo , Criança , Epitélio/metabolismo , Humanos , Metaplasia/metabolismo , Mucina-5AC/genética , Mucina-5AC/metabolismo , Muco/metabolismo
3.
Polymers (Basel) ; 14(6)2022 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-35335482

RESUMO

With the increasing interest in hydrogen energy, the stability of hydrogen storage facilities and components is emphasized. In this study, we analyzed the effect of high-pressure hydrogen gas treatment in silica-filled EPDM composites with different silica contents. In detail, cure characteristics, crosslink density, mechanical properties, and hydrogen permeation properties were investigated. Results showed that material volume, remaining hydrogen content, and mechanical properties were changed after 96.3 MPa hydrogen gas exposure. With an increase in the silica content, the crosslink density and mechanical properties increased, but hydrogen permeability was decreased. After treatment, high-silica-content composites showed lower volume change than low-silica-content composites. The crack damage due to the decompression caused a decrease in mechanical properties, but high silica content can inhibit the reduction in mechanical properties. In particular, EPDM/silica composites with a silica content of above 60 phr exhibited excellent resistance to hydrogen gas, as no change in their physical and mechanical properties was observed.

4.
PLoS Genet ; 18(1): e1009571, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35100255

RESUMO

Transcriptome wide association studies (TWAS) can be used as a powerful method to identify and interpret the underlying biological mechanisms behind GWAS by mapping gene expression levels with phenotypes. In TWAS, gene expression is often imputed from individual-level genotypes of regulatory variants identified from external resources, such as Genotype-Tissue Expression (GTEx) Project. In this setting, a straightforward approach to impute expression levels of a specific tissue is to use the model trained from the same tissue type. When multiple tissues are available for the same subjects, it has been demonstrated that training imputation models from multiple tissue types improves the accuracy because of shared eQTLs between the tissues and increase in effective sample size. However, existing joint-tissue methods require access of genotype and expression data across all tissues. Moreover, they cannot leverage the abundance of various expression datasets across various tissues for non-overlapping individuals. Here, we explore the optimal way to combine imputed levels across training models from multiple tissues and datasets in a flexible manner using summary-level data. Our proposed method (SWAM) combines arbitrary number of transcriptome imputation models to linearly optimize the imputation accuracy given a target tissue. By integrating models across tissues and/or individuals, SWAM can improve the accuracy of transcriptome imputation or to improve power to TWAS while only requiring individual-level data from a single reference cohort. To evaluate the accuracy of SWAM, we combined 49 tissue-specific gene expression imputation models from the GTEx Project as well as from a large eQTL study of Depression Susceptibility Genes and Networks (DGN) Project and tested imputation accuracy in GEUVADIS lymphoblastoid cell lines samples. We also extend our meta-imputation method to meta-TWAS to leverage multiple tissues in TWAS analysis with summary-level statistics. Our results capitalize on the importance of integrating multiple tissues to unravel regulatory impacts of genetic variants on complex traits.


Assuntos
Conjuntos de Dados como Assunto , Genótipo , Modelos Genéticos , Transcriptoma , Estudo de Associação Genômica Ampla/métodos , Humanos , Análise da Randomização Mendeliana , Locos de Características Quantitativas
5.
J Vet Sci ; 22(6): e77, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34697923

RESUMO

BACKGROUND: Serum-based parameters are considered non-invasive biomarkers for cancer detection. In human studies, insulin-like growth factor-I and II (IGF-I and IGF-II) and insulin-like growth factor binding protein-3 (IGFBP-3) are useful as diagnostic or prognostic markers and potential therapeutic targets. OBJECTIVES: This study examined the diagnostic utility of circulating IGF-I, IGF-II, and IGFBP-3 levels in healthy dogs and dogs with tumors. METHODS: The serum concentrations of these biomarkers in 86 dogs with tumors were compared with those in 30 healthy dogs using an enzyme-linked immunosorbent assay (ELISA). RESULTS: The ELISA results showed no difference between healthy dogs and dogs with tumors in the serum IGF-II concentrations. On the other hand, there was a significant difference in the circulating IGF-I and IGFBP-3 levels between healthy dogs and dogs with tumors. The concentrations of serum IGF-I (median [interquartile range], 103.4 [59.5-175] ng/mL) in dogs with epithelial tumors were higher than those (58.4 ng/mL [43.5-79.9]) in healthy dogs. Thus, the concentrations of serum IGFBP-3 (43.4 ng/mL [33.2-57.2]) in dogs with malignant mesenchymal tumors were lower than those (60.8 ng/mL [47.6-70.5]) in healthy dogs. CONCLUSIONS: The serum IGF-I and IGFBP-3 levels can be used as diagnostic biomarkers in dogs with tumors.


Assuntos
Doenças do Cão , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Neoplasias , Animais , Biomarcadores/sangue , Doenças do Cão/diagnóstico , Cães , Neoplasias/diagnóstico , Neoplasias/veterinária
6.
Bioinformatics ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34459872

RESUMO

SUMMARY: Expression quantitative trait loci (eQTLs) characterize the associations between genetic variation and gene expression to provide insights into tissue-specific gene regulation. Interactive visualization of tissue-specific eQTLs or splice QTLs (sQTLs) can facilitate our understanding of functional variants relevant to disease-related traits. However, combining the multi-dimensional nature of eQTLs/sQTLs into a concise and informative visualization is challenging. Existing QTL visualization tools provide useful ways to summarize the unprecedented scale of transcriptomic data but are not necessarily tailored to answer questions about the functional interpretations of trait-associated variants or other variants of interest. We developed FIVEx, an interactive eQTL/sQTL browser with an intuitive interface tailored to the functional interpretation of associated variants. It features the ability to navigate seamlessly between different data views while providing relevant tissue- and locus-specific information to offer users a better understanding of population-scale multi-tissue transcriptomic profiles. Our implementation of the FIVEx browser on the EBI eQTL catalogue, encompassing 16 publicly available RNA-seq studies, provides important insights for understanding potential tissue-specific regulatory mechanisms underlying trait-associated signals. AVAILABILITY AND IMPLEMENTATION: A FIVEx instance visualizing EBI eQTL catalogue data can be found at https://fivex.sph.umich.edu. Its source code is open source under an MIT license at https://github.com/statgen/fivex. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

7.
PLoS One ; 16(7): e0253611, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34214102

RESUMO

Handgrip strength is a widely used measure of muscle strength and a predictor of a range of morbidities including cardiovascular diseases and all-cause mortality. Previous genome-wide association studies of handgrip strength have focused on common variants primarily in persons of European descent. We aimed to identify rare and ancestry-specific genetic variants associated with handgrip strength by conducting whole-genome sequence association analyses using 13,552 participants from six studies representing diverse population groups from the Trans-Omics in Precision Medicine (TOPMed) Program. By leveraging multiple handgrip strength measures performed in study participants over time, we increased our effective sample size by 7-12%. Single-variant analyses identified ten handgrip strength loci among African-Americans: four rare variants, five low-frequency variants, and one common variant. One significant and four suggestive genes were identified associated with handgrip strength when aggregating rare and functional variants; all associations were ancestry-specific. We additionally leveraged the different ancestries available in the UK Biobank to further explore the ancestry-specific association signals from the single-variant association analyses. In conclusion, our study identified 11 new loci associated with handgrip strength with rare and/or ancestry-specific genetic variations, highlighting the added value of whole-genome sequencing in diverse samples. Several of the associations identified using single-variant or aggregate analyses lie in genes with a function relevant to the brain or muscle or were reported to be associated with muscle or age-related traits. Further studies in samples with sequence data and diverse ancestries are needed to confirm these findings.


Assuntos
Força da Mão/fisiologia , Sequenciamento Completo do Genoma/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Medicina de Precisão/estatística & dados numéricos , /estatística & dados numéricos
8.
Cell ; 184(13): 3559-3572.e22, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34115981

RESUMO

Spatial barcoding technologies have the potential to reveal histological details of transcriptomic profiles; however, they are currently limited by their low resolution. Here, we report Seq-Scope, a spatial barcoding technology with a resolution comparable to an optical microscope. Seq-Scope is based on a solid-phase amplification of randomly barcoded single-molecule oligonucleotides using an Illumina sequencing platform. The resulting clusters annotated with spatial coordinates are processed to expose RNA-capture moiety. These RNA-capturing barcoded clusters define the pixels of Seq-Scope that are ∼0.5-0.8 µm apart from each other. From tissue sections, Seq-Scope visualizes spatial transcriptome heterogeneity at multiple histological scales, including tissue zonation according to the portal-central (liver), crypt-surface (colon) and inflammation-fibrosis (injured liver) axes, cellular components including single-cell types and subtypes, and subcellular architectures of nucleus and cytoplasm. Seq-Scope is quick, straightforward, precise, and easy-to-implement and makes spatial single-cell analysis accessible to a wide group of biomedical researchers.


Assuntos
Microscopia , Transcriptoma/genética , Animais , Núcleo Celular/genética , Colo/patologia , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Inflamação/genética , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , RNA/metabolismo , Análise de Célula Única
9.
Bioinformatics ; 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33989384

RESUMO

SUMMARY: The sparse allele vectors (SAV) file format is an efficient storage format for large-scale DNA variation data and is designed for high throughput association analysis by leveraging techniques for fast deserialization of data into computer memory. A command line interface has been developed to complement the storage format and supports basic features like importing, exporting and subsetting. Additionally, a C ++ programming API is available allowing for easy integration into analysis software. AVAILABILITY AND IMPLEMENTATION: https://github.com/statgen/savvy. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

10.
Bioinformatics ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33760063

RESUMO

MOTIVATION: There are high demands for joint genotyping of structural variations with short-read sequencing, but efficient and accurate genotyping in population scale is a challenging task. RESULTS: We developed muCNV that aggregates per-sample summary pileups for joint genotyping of > 100,000 samples. Pilot results show very low Mendelian inconsistencies. Applications to large-scale projects in cloud show the computational efficiencies of muCNV genotyping pipeline. AVAILABILITY: muCNV is publicly available for download at: https://github.com/gjun/muCNV. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

12.
Genetics ; 218(1)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33720349

RESUMO

Traditional Hardy-Weinberg equilibrium (HWE) tests (the χ2 test and the exact test) have long been used as a metric for evaluating genotype quality, as technical artifacts leading to incorrect genotype calls often can be identified as deviations from HWE. However, in data sets composed of individuals from diverse ancestries, HWE can be violated even without genotyping error, complicating the use of HWE testing to assess genotype data quality. In this manuscript, we present the Robust Unified Test for HWE (RUTH) to test for HWE while accounting for population structure and genotype uncertainty, and to evaluate the impact of population heterogeneity and genotype uncertainty on the standard HWE tests and alternative methods using simulated and real sequence data sets. Our results demonstrate that ignoring population structure or genotype uncertainty in HWE tests can inflate false-positive rates by many orders of magnitude. Our evaluations demonstrate different tradeoffs between false positives and statistical power across the methods, with RUTH consistently among the best across all evaluations. RUTH is implemented as a practical and scalable software tool to rapidly perform HWE tests across millions of markers and hundreds of thousands of individuals while supporting standard VCF/BCF formats. RUTH is publicly available at https://www.github.com/statgen/ruth.


Assuntos
Frequência do Gene/genética , Genética Populacional/métodos , Desequilíbrio de Ligação/genética , Alelos , Genótipo , Humanos , Modelos Genéticos , Modelos Estatísticos , Fenótipo , Software
13.
Gut ; 70(7): 1325-1334, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33632709

RESUMO

OBJECTIVE: An understanding of the etiologic heterogeneity of colorectal cancer (CRC) is critical for improving precision prevention, including individualized screening recommendations and the discovery of novel drug targets and repurposable drug candidates for chemoprevention. Known differences in molecular characteristics and environmental risk factors among tumors arising in different locations of the colorectum suggest partly distinct mechanisms of carcinogenesis. The extent to which the contribution of inherited genetic risk factors for CRC differs by anatomical subsite of the primary tumor has not been examined. DESIGN: To identify new anatomical subsite-specific risk loci, we performed genome-wide association study (GWAS) meta-analyses including data of 48 214 CRC cases and 64 159 controls of European ancestry. We characterised effect heterogeneity at CRC risk loci using multinomial modelling. RESULTS: We identified 13 loci that reached genome-wide significance (p<5×10-8) and that were not reported by previous GWASs for overall CRC risk. Multiple lines of evidence support candidate genes at several of these loci. We detected substantial heterogeneity between anatomical subsites. Just over half (61) of 109 known and new risk variants showed no evidence for heterogeneity. In contrast, 22 variants showed association with distal CRC (including rectal cancer), but no evidence for association or an attenuated association with proximal CRC. For two loci, there was strong evidence for effects confined to proximal colon cancer. CONCLUSION: Genetic architectures of proximal and distal CRC are partly distinct. Studies of risk factors and mechanisms of carcinogenesis, and precision prevention strategies should take into consideration the anatomical subsite of the tumour.


Assuntos
Colo , Neoplasias do Colo/genética , Heterogeneidade Genética , Neoplasias Retais/genética , Adulto , Distribuição por Idade , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Ceco , Colo Ascendente , Colo Descendente , Colo Sigmoide , Colo Transverso , Neoplasias do Colo/diagnóstico , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Neoplasias Retais/diagnóstico , Fatores de Risco , Adulto Jovem
14.
Nature ; 590(7845): 290-299, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568819

RESUMO

The Trans-Omics for Precision Medicine (TOPMed) programme seeks to elucidate the genetic architecture and biology of heart, lung, blood and sleep disorders, with the ultimate goal of improving diagnosis, treatment and prevention of these diseases. The initial phases of the programme focused on whole-genome sequencing of individuals with rich phenotypic data and diverse backgrounds. Here we describe the TOPMed goals and design as well as the available resources and early insights obtained from the sequence data. The resources include a variant browser, a genotype imputation server, and genomic and phenotypic data that are available through dbGaP (Database of Genotypes and Phenotypes)1. In the first 53,831 TOPMed samples, we detected more than 400 million single-nucleotide and insertion or deletion variants after alignment with the reference genome. Additional previously undescribed variants were detected through assembly of unmapped reads and customized analysis in highly variable loci. Among the more than 400 million detected variants, 97% have frequencies of less than 1% and 46% are singletons that are present in only one individual (53% among unrelated individuals). These rare variants provide insights into mutational processes and recent human evolutionary history. The extensive catalogue of genetic variation in TOPMed studies provides unique opportunities for exploring the contributions of rare and noncoding sequence variants to phenotypic variation. Furthermore, combining TOPMed haplotypes with modern imputation methods improves the power and reach of genome-wide association studies to include variants down to a frequency of approximately 0.01%.


Assuntos
Variação Genética/genética , Genoma Humano/genética , Genômica , National Heart, Lung, and Blood Institute (U.S.) , Medicina de Precisão , Citocromo P-450 CYP2D6/genética , Haplótipos/genética , Heterozigoto , Humanos , Mutação INDEL , Mutação com Perda de Função , Mutagênese , Fenótipo , Polimorfismo de Nucleotídeo Único , Densidade Demográfica , Medicina de Precisão/normas , Controle de Qualidade , Tamanho da Amostra , Estados Unidos , Sequenciamento Completo do Genoma/normas
15.
Mol Psychiatry ; 26(9): 5239-5250, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33483695

RESUMO

Bipolar disorder (BD) is a serious mental illness with substantial common variant heritability. However, the role of rare coding variation in BD is not well established. We examined the protein-coding (exonic) sequences of 3,987 unrelated individuals with BD and 5,322 controls of predominantly European ancestry across four cohorts from the Bipolar Sequencing Consortium (BSC). We assessed the burden of rare, protein-altering, single nucleotide variants classified as pathogenic or likely pathogenic (P-LP) both exome-wide and within several groups of genes with phenotypic or biologic plausibility in BD. While we observed an increased burden of rare coding P-LP variants within 165 genes identified as BD GWAS regions in 3,987 BD cases (meta-analysis OR = 1.9, 95% CI = 1.3-2.8, one-sided p = 6.0 × 10-4), this enrichment did not replicate in an additional 9,929 BD cases and 14,018 controls (OR = 0.9, one-side p = 0.70). Although BD shares common variant heritability with schizophrenia, in the BSC sample we did not observe a significant enrichment of P-LP variants in SCZ GWAS genes, in two classes of neuronal synaptic genes (RBFOX2 and FMRP) associated with SCZ or in loss-of-function intolerant genes. In this study, the largest analysis of exonic variation in BD, individuals with BD do not carry a replicable enrichment of rare P-LP variants across the exome or in any of several groups of genes with biologic plausibility. Moreover, despite a strong shared susceptibility between BD and SCZ through common genetic variation, we do not observe an association between BD risk and rare P-LP coding variants in genes known to modulate risk for SCZ.


Assuntos
Transtorno Bipolar , Esquizofrenia , Transtorno Bipolar/genética , Exoma/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética
16.
Gigascience ; 10(2)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33511994

RESUMO

BACKGROUND: Rapid and thorough quality assessment of sequenced genomes on an ultra-high-throughput scale is crucial for successful large-scale genomic studies. Comprehensive quality assessment typically requires full genome alignment, which costs a substantial amount of computational resources and turnaround time. Existing tools are either computationally expensive owing to full alignment or lacking essential quality metrics by skipping read alignment. FINDINGS: We developed a set of rapid and accurate methods to produce comprehensive quality metrics directly from a subset of raw sequence reads (from whole-genome or whole-exome sequencing) without full alignment. Our methods offer orders of magnitude faster turnaround time than existing full alignment-based methods while providing comprehensive and sophisticated quality metrics, including estimates of genetic ancestry and cross-sample contamination. CONCLUSIONS: By rapidly and comprehensively performing the quality assessment, our tool will help investigators detect potential issues in ultra-high-throughput sequence reads in real time within a low computational cost at the early stages of the analyses, ensuring high-quality downstream results and preventing unexpected loss in time, money, and invaluable specimens.


Assuntos
Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Software , Sequenciamento Completo do Exoma
17.
Am J Respir Crit Care Med ; 203(4): 424-436, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-32966749

RESUMO

Rationale: The 17q12-21.1 locus is one of the most highly replicated genetic associations with asthma. Individuals of African descent have lower linkage disequilibrium in this region, which could facilitate identifying causal variants.Objectives: To identify functional variants at 17q12-21.1 associated with early-onset asthma among African American individuals.Methods: We evaluated African American participants from SAPPHIRE (Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity) (n = 1,940), SAGE II (Study of African Americans, Asthma, Genes and Environment) (n = 885), and GCPD-A (Study of the Genetic Causes of Complex Pediatric Disorders-Asthma) (n = 2,805). Associations with asthma onset at ages under 5 years were meta-analyzed across cohorts. The lead signal was reevaluated considering haplotypes informed by genetic ancestry (i.e., African vs. European). Both an expression-quantitative trait locus analysis and a phenome-wide association study were performed on the lead variant.Measurements and Main Results: The meta-analyzed results from SAPPHIRE, SAGE II, and the GCPD-A identified rs11078928 as the top association for early-onset asthma. A haplotype analysis suggested that the asthma association partitioned most closely with the rs11078928 genotype. Genetic ancestry did not appear to influence the effect of this variant. In the expression-quantitative trait locus analysis, rs11078928 was related to alternative splicing of GSDMB (gasdermin-B) transcripts. The phenome-wide association study of rs11078928 suggested that this variant was predominantly associated with asthma and asthma-associated symptoms.Conclusions: A splice-acceptor polymorphism appears to be a causal variant for asthma at the 17q12-21.1 locus. This variant appears to have the same magnitude of effect in individuals of African and European descent.


Assuntos
Afro-Americanos/genética , Cromossomos Humanos Par 17 , Estudos de Associação Genética , Predisposição Genética para Doença/genética , /genética , Adolescente , Adulto , Idade de Início , Asma/genética , Criança , Pré-Escolar , Mapeamento Cromossômico , Feminino , Variação Genética , Humanos , Lactente , Recém-Nascido , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Estados Unidos , Adulto Jovem
18.
Gastroenterology ; 160(4): 1164-1178.e6, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33058866

RESUMO

BACKGROUND AND AIMS: Susceptibility genes and the underlying mechanisms for the majority of risk loci identified by genome-wide association studies (GWAS) for colorectal cancer (CRC) risk remain largely unknown. We conducted a transcriptome-wide association study (TWAS) to identify putative susceptibility genes. METHODS: Gene-expression prediction models were built using transcriptome and genetic data from the 284 normal transverse colon tissues of European descendants from the Genotype-Tissue Expression (GTEx), and model performance was evaluated using data from The Cancer Genome Atlas (n = 355). We applied the gene-expression prediction models and GWAS data to evaluate associations of genetically predicted gene-expression with CRC risk in 58,131 CRC cases and 67,347 controls of European ancestry. Dual-luciferase reporter assays and knockdown experiments in CRC cells and tumor xenografts were conducted. RESULTS: We identified 25 genes associated with CRC risk at a Bonferroni-corrected threshold of P < 9.1 × 10-6, including genes in 4 novel loci, PYGL (14q22.1), RPL28 (19q13.42), CAPN12 (19q13.2), MYH7B (20q11.22), and MAP1L3CA (20q11.22). In 9 known GWAS-identified loci, we uncovered 9 genes that have not been reported previously, whereas 4 genes remained statistically significant after adjusting for the lead risk variant of the locus. Through colocalization analysis in GWAS loci, we additionally identified 12 putative susceptibility genes that were supported by TWAS analysis at P < .01. We showed that risk allele of the lead risk variant rs1741640 affected the promoter activity of CABLES2. Knockdown experiments confirmed that CABLES2 plays a vital role in colorectal carcinogenesis. CONCLUSIONS: Our study reveals new putative susceptibility genes and provides new insight into the biological mechanisms underlying CRC development.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Modelos Genéticos , Alelos , Carcinogênese/genética , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias Colorretais/epidemiologia , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , RNA-Seq , Fatores de Risco , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Am J Physiol Endocrinol Metab ; 320(2): E244-E258, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33103450

RESUMO

During nutritional overload and obesity, hepatocyte function is grossly altered, and a subset of hepatocytes begins to accumulate fat droplets, leading to nonalcoholic fatty liver disease (NAFLD). Recent single-cell studies revealed how nonparenchymal cells, such as macrophages, hepatic stellate cells, and endothelial cells, heterogeneously respond to NAFLD. However, it remains to be characterized how hepatocytes, the major constituents of the liver, respond to nutritional overload in NAFLD. Here, using droplet-based, single-cell RNA sequencing (Drop-seq), we characterized how the transcriptomic landscape of individual hepatocytes is altered in response to high-fat diet (HFD) and NAFLD. We showed that the entire hepatocyte population undergoes substantial transcriptome changes upon HFD, although the patterns of alteration were highly heterogeneous, with zonation-dependent and -independent effects. Periportal (zone 1) hepatocytes downregulated many zone 1-specific marker genes, whereas a small number of genes mediating gluconeogenesis were upregulated. Pericentral (zone 3) hepatocytes also downregulated many zone 3-specific genes; however, they upregulated several genes that promote HFD-induced fat droplet formation, consistent with findings that zone 3 hepatocytes accumulate more lipid droplets. Zone 3 hepatocytes also upregulated ketogenic pathways as an adaptive mechanism to HFD. Interestingly, many of the top HFD-induced genes, which encode proteins regulating lipid metabolism, were strongly co-expressed with each other in a subset of hepatocytes, producing a variegated pattern of spatial co-localization that is independent of metabolic zonation. In conclusion, our data set provides a useful resource for understanding hepatocellular alteration during NAFLD at single cell level.


Assuntos
Dieta Hiperlipídica , Gorduras na Dieta/farmacologia , Hepatócitos , Transcriptoma/efeitos dos fármacos , Animais , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Análise de Célula Única/métodos , Magreza/genética , Magreza/metabolismo , Magreza/patologia
20.
PLoS Genet ; 16(12): e1009060, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33320851

RESUMO

Gene-based association tests aggregate genotypes across multiple variants for each gene, providing an interpretable gene-level analysis framework for genome-wide association studies (GWAS). Early gene-based test applications often focused on rare coding variants; a more recent wave of gene-based methods, e.g. TWAS, use eQTLs to interrogate regulatory associations. Regulatory variants are expected to be particularly valuable for gene-based analysis, since most GWAS associations to date are non-coding. However, identifying causal genes from regulatory associations remains challenging and contentious. Here, we present a statistical framework and computational tool to integrate heterogeneous annotations with GWAS summary statistics for gene-based analysis, applied with comprehensive coding and tissue-specific regulatory annotations. We compare power and accuracy identifying causal genes across single-annotation, omnibus, and annotation-agnostic gene-based tests in simulation studies and an analysis of 128 traits from the UK Biobank, and find that incorporating heterogeneous annotations in gene-based association analysis increases power and performance identifying causal genes.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Anotação de Sequência Molecular/métodos , Algoritmos , Estudo de Associação Genômica Ampla/normas , Humanos , Anotação de Sequência Molecular/normas , Polimorfismo Genético , Locos de Características Quantitativas , Reprodutibilidade dos Testes
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