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2.
Nat Commun ; 12(1): 3447, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103494

RESUMO

Congenital heart disease (CHD) is the most common class of human birth defects, with a prevalence of 0.9% of births. However, two-thirds of cases have an unknown cause, and many of these are thought to be caused by in utero exposure to environmental teratogens. Here we identify a potential teratogen causing CHD in mice: maternal iron deficiency (ID). We show that maternal ID in mice causes severe cardiovascular defects in the offspring. These defects likely arise from increased retinoic acid signalling in ID embryos. The defects can be prevented by iron administration in early pregnancy. It has also been proposed that teratogen exposure may potentiate the effects of genetic predisposition to CHD through gene-environment interaction. Here we show that maternal ID increases the severity of heart and craniofacial defects in a mouse model of Down syndrome. It will be important to understand if the effects of maternal ID seen here in mice may have clinical implications for women.


Assuntos
Sistema Cardiovascular/embriologia , Embrião de Mamíferos/patologia , Ferro/deficiência , Animais , Aorta Torácica/anormalidades , Biomarcadores/metabolismo , Diferenciação Celular , Vasos Coronários/embriologia , Vasos Coronários/patologia , Suplementos Nutricionais , Edema/patologia , Embrião de Mamíferos/anormalidades , Desenvolvimento Embrionário , Feminino , Perfilação da Expressão Gênica , Interação Gene-Ambiente , Proteínas de Fluorescência Verde/metabolismo , Ferro/metabolismo , Vasos Linfáticos/embriologia , Vasos Linfáticos/patologia , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Penetrância , Fenótipo , Gravidez , Transdução de Sinais , Células-Tronco/patologia , Transgenes , Tretinoína/metabolismo
3.
Nat Commun ; 12(1): 3505, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108472

RESUMO

Hundreds of thousands of genetic variants have been reported to cause severe monogenic diseases, but the probability that a variant carrier develops the disease (termed penetrance) is unknown for virtually all of them. Additionally, the clinical utility of common polygenetic variation remains uncertain. Using exome sequencing from 77,184 adult individuals (38,618 multi-ancestral individuals from a type 2 diabetes case-control study and 38,566 participants from the UK Biobank, for whom genotype array data were also available), we apply clinical standard-of-care gene variant curation for eight monogenic metabolic conditions. Rare variants causing monogenic diabetes and dyslipidemias display effect sizes significantly larger than the top 1% of the corresponding polygenic scores. Nevertheless, penetrance estimates for monogenic variant carriers average 60% or lower for most conditions. We assess epidemiologic and genetic factors contributing to risk prediction in monogenic variant carriers, demonstrating that inclusion of polygenic variation significantly improves biomarker estimation for two monogenic dyslipidemias.


Assuntos
Diabetes Mellitus Tipo 2/genética , Dislipidemias/genética , Predisposição Genética para Doença/genética , Adulto , Variação Biológica da População , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/metabolismo , Exoma/genética , Genótipo , Humanos , Herança Multifatorial , Penetrância , Medição de Risco
4.
Adv Exp Med Biol ; 1187: 419-434, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983592

RESUMO

Susceptibility genes involved in disease etiology and prognosis are categorized into two groups: high penetrance genes (i.e., BRCA1, CHEK2, ATM, etc.) and low penetrance genes (i.e., NATs, GSTs, CYPs, etc., and variants identified by genome-wide association studies). Since low penetrance genes have high population attributable risk, the usefulness of those genes to research on breast cancer prevention is not small. In this chapter, the previous studies on low-penetrance genetic susceptibility through a candidate gene approach and genome-wide association of breast cancer were summarized. The contribution of low-penetrance susceptibility genes to the breast cancer risk prediction models will also be discussed on the utility in clinical or public health application.


Assuntos
Neoplasias da Mama , Estudo de Associação Genômica Ampla , Neoplasias da Mama/genética , Predisposição Genética para Doença , Humanos , Penetrância
5.
Adv Exp Med Biol ; 1187: 473-490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983595

RESUMO

Genetic susceptibility explains 5-10% of all breast cancer cases. High-penetrance breast cancer susceptibility genes deliberate a greater than tenfold relative risk of breast cancer. BRCA1 and BRCA2 genes are the most common cause of hereditary breast cancer, and TP53, PTEN, and SKT11 (LKB1) are rarely present. The prevalence of BRCA1 and BRCA2 genetic alterations differ in various ethnic groups. The Korean Hereditary Breast Cancer (KOHBRA) Study, nationwide-scale study, was established to acquire evidence for the accurate risk assessment and management of hereditary breast and ovarian cancer (HBOC) in Korea prospectively since 2007. In this chapter, we review previous research related to hereditary breast cancer and summarize the present concepts and research results centered on the Korean Hereditary Breast Cancer Research at this time.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias da Mama/genética , Feminino , Genes BRCA2 , Predisposição Genética para Doença , Humanos , Mutação , Neoplasias Ovarianas/genética , Penetrância , República da Coreia
6.
Bull Cancer ; 108(7-8): 718-724, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34052033

RESUMO

Genetic predisposition has been always noted in the context of familial hematological malignancies. Epidemiological studies have provided evidence consisting of an increased risk to develop blood cancer in relatives diagnosed with the same pathology and characterized by early age at diagnosis and higher severity compared to sporadic forms. With the emergence of new genomic testing approaches, the prevalence of familial aggregations of hematological malignancies seems to be under estimated. The heterogeneity of clinical features explains the wide number of genes' mutations reported to date and the variable penetrance of variants. Nevertheless, the genetic basis of familial hematological malignancies is still not well understood. Identifying the genetic background in familial aggregations provides a valuable tool for prognostic evaluation, personalized treatment and better genetic counseling in high-risk families. Herein, we provide an overview of genes reported in the last few years in association to hematological malignancies including familial form of Hodgkin Lymphoma, Non-Hodgkin Lymphoma, Chronic Lymphocytic Leukemia, acute Myeloid Leukemia and acute Lymphoblastic Leukemia.


Assuntos
Predisposição Genética para Doença , Neoplasias Hematológicas/genética , Fatores Etários , Família , Neoplasias Hematológicas/epidemiologia , Doença de Hodgkin/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Mieloide Aguda/genética , Linfoma não Hodgkin/genética , Mutação , Penetrância , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico
7.
Nat Commun ; 12(1): 2850, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33990600

RESUMO

Functional assessment of disease-associated sequence variation at non-coding regulatory elements is complicated by their high degree of context sensitivity to both the local chromatin and nuclear environments. Allelic profiling of DNA accessibility across individuals has shown that only a select minority of sequence variation affects transcription factor (TF) occupancy, yet low sequence diversity in human populations means that no experimental assessment is available for the majority of disease-associated variants. Here we describe high-resolution in vivo maps of allelic DNA accessibility in liver, kidney, lung and B cells from 5 increasingly diverged strains of F1 hybrid mice. The high density of heterozygous sites in these hybrids enables precise quantification of effect size and cell-type specificity for hundreds of thousands of variants throughout the mouse genome. We show that chromatin-altering variants delineate characteristic sensitivity profiles for hundreds of TF motifs. We develop a compendium of TF-specific sensitivity profiles accounting for genomic context effects. Finally, we link maps of allelic accessibility to allelic transcript levels in the same samples. This work provides a foundation for quantitative prediction of cell-type specific effects of non-coding variation on TF activity, which will facilitate both fine-mapping and systems-level analyses of common disease-associated variation in human genomes.


Assuntos
DNA/genética , Alelos , Animais , Sítios de Ligação/genética , Cromatina/genética , Cromatina/metabolismo , Mapeamento Cromossômico , DNA/metabolismo , Feminino , Regulação da Expressão Gênica , Variação Genética , Genoma Humano , Humanos , Hibridização Genética , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Penetrância , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo
8.
Nat Commun ; 12(1): 3216, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050153

RESUMO

X-linked dystonia-parkinsonism is a neurodegenerative disorder caused by a founder retrotransposon insertion, in which a polymorphic hexanucleotide repeat accounts for ~50% of age at onset variability. Employing a genome-wide association study to identify additional factors modifying age at onset, we establish that three independent loci are significantly associated with age at onset (p < 5 × 10-8). The lead single nucleotide polymorphisms collectively account for 25.6% of the remaining variance not explained by the hexanucleotide repeat and 13.0% of the overall variance in age at onset in X-linked dystonia-parkinsonism with the protective alleles delaying disease onset by seven years. These regions harbor or lie adjacent to MSH3 and PMS2, the genes that were recently implicated in modifying age at onset in Huntington's disease, likely through a common pathway influencing repeat instability. Our work indicates the existence of three modifiers of age at onset in X-linked dystonia-parkinsonism that likely affect the DNA mismatch repair pathway.


Assuntos
Distúrbios Distônicos/genética , Genes Modificadores , Doenças Genéticas Ligadas ao Cromossomo X/genética , Loci Gênicos , Penetrância , Adulto , Idade de Início , Idoso , Alelos , Estudos de Casos e Controles , Reparo de Erro de Pareamento de DNA , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Proteção , Adulto Jovem
9.
Nat Commun ; 12(1): 2047, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824349

RESUMO

Human chromosome 9p21.3 is susceptible to inactivation in cell immortalization and diseases, such as cancer, coronary artery disease and type-2 diabetes. Although this locus encodes three cyclin-dependent kinase (CDK) inhibitors (p15INK4B, p14ARF and p16INK4A), our understanding of their functions and modes of action is limited to the latter two. Here, we show that in vitro p15INK4B is markedly stronger than p16INK4A in inhibiting pRb1 phosphorylation, E2F activity and cell-cycle progression. In mice, urothelial cells expressing oncogenic HRas and lacking p15INK4B, but not those expressing HRas and lacking p16INK4A, develop early-onset bladder tumors. The potency of CDKN2B/p15INK4B in tumor suppression relies on its strong binding via key N-terminal residues to and inhibition of CDK4/CDK6. p15INK4B also binds and inhibits enolase-1, a glycolytic enzyme upregulated in most cancer types. Our results highlight the dual inhibition of p15INK4B on cell proliferation, and unveil mechanisms whereby p15INK4B aberrations may underpin cancer and non-cancer conditions.


Assuntos
Ciclo Celular , Cromossomos de Mamíferos/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Glicólise , Aerobiose , Sequência de Aminoácidos , Animais , Ligação Competitiva , Cruzamento , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células , Cruzamentos Genéticos , Inibidor de Quinase Dependente de Ciclina p15/química , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo , Feminino , Humanos , Ligação de Hidrogênio , Masculino , Camundongos Transgênicos , Modelos Moleculares , Oncogenes , Penetrância , Fosfopiruvato Hidratase/metabolismo , Domínios Proteicos , Proteínas Proto-Oncogênicas p21(ras) , Homologia Estrutural de Proteína , Neoplasias da Bexiga Urinária/patologia , Urotélio/metabolismo
10.
J Proteome Res ; 20(5): 2704-2713, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33719450

RESUMO

Much of our understanding of proteins and proteomes comes from the traditional protein structure-function paradigm. However, in the last 2 decades, both computational and experimental studies have provided evidence that a large fraction of functional proteomes across different domains of life consists of intrinsically disordered proteins, thus triggering a quest to unravel and decipher protein intrinsic disorder. Unlike structured/ordered proteins, intrinsically disordered proteins/regions (IDPs/IDRs) do not possess a well-defined structure under physiological conditions and exist as highly dynamic conformational ensembles. In spite of this peculiarity, these proteins have crucial roles in cell signaling and regulation. To date, studies on the abundance and function of IDPs/IDRs in viruses are rather limited. To fill this gap, we carried out an extensive and thorough bioinformatics analysis of 283 000 proteins from 6108 reference viral proteomes. We analyzed protein intrinsic disorder from multiple perspectives, such as abundance of IDPs/IDRs across diverse virus types, their functional annotations, and subcellular localization in taxonomically divergent hosts. We show that the content of IDPs/IDRs in viral proteomes varies broadly as a function of virus genome types and taxonomically divergent hosts. We have combined the two most commonly used and accurate IDP predictors' results with charge-hydropathy (CH) versus cumulative distribution function (CDF) plots to categorize the viral proteins according to their IDR content and physicochemical properties. Mapping of gene ontology on the disorder content of viral proteins reveals that IDPs are primarily involved in key virus-host interactions and host antiviral immune response downregulation, which are reinforced by the post-translational modifications tied to disorder-enriched viral proteins. The present study offers detailed insights into the prevalence of the intrinsic disorder in viral proteomes and provides appealing targets for the design of novel therapeutics.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteoma , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Penetrância , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteoma/genética , Proteínas Virais/genética
11.
Medicine (Baltimore) ; 100(12): e25171, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33761695

RESUMO

RATIONALE: Acute necrotizing encephalopathy (ANE) is a specific type of encephalopathy usually followed by febrile infection. It has an aggressive clinical course; however, it usually does not recur after recovery in cases of spontaneous ANE. Nevertheless, there are several studies reporting recurrences in familial ANE with RAN-binding protein 2 (RANBP2) mutation. There are few cases of familial ANE with RANBP2 mutation in Asian populations. PATIENTS CONCERNS: A 21-month-old Korean boy who was previously healthy, presented with seizure following parainfluenza - a virus and bocavirus infection, followed by 2 recurrent seizure episodes and encephalitis after febrile respiratory illnesses. Meanwhile, his 3-year-old sister had focal brain lesions on neuroimaging studies when evaluated for head trauma. The siblings also had an older brother who presented status epilepticus after febrile respiratory illness at the age of 10 months old. DIAGNOSIS: Brain magnetic resonance imaging was performed to evaluate the seizure and neurologic symptoms. Imaging findings showed variable spectrum - from non-specific diffuse white matter injury pattern to typical "tricolor pattern" of the ANE on diffusion-weighted images. The other 2 siblings showed focal lesions in both external capsules and severe diffuse brain edema. Genetic tests identified a heterozygous missense mutation in the RANBP2 [c.1754C>T (p.Thr585Met)] in 2 siblings and their mother. INTERVENTIONS: Patients were treated conservatively with anticonvulsive agents, intravascular immunoglobulin, and steroids. OUTCOMES: Among the 3 siblings, 2 male siblings died from familial ANE, whereas the female sibling was asymptomatic. LESSONS: These cases highlight the radiological aspects of familial ANE with incomplete penetrance of the RANBP2 gene in 3 family members, showing variable involvements of the brain and natural history on magnetic resonance images. Radiologists should be aware of the typical and atypical imaging findings of familial ANE for prompt management of affected patients.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Leucoencefalite Hemorrágica Aguda/diagnóstico por imagem , Leucoencefalite Hemorrágica Aguda/genética , Chaperonas Moleculares/genética , Mutação de Sentido Incorreto , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Corticosteroides/uso terapêutico , Anticonvulsivantes/uso terapêutico , Pré-Escolar , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Leucoencefalite Hemorrágica Aguda/complicações , Leucoencefalite Hemorrágica Aguda/tratamento farmacológico , Masculino , Penetrância , Convulsões/tratamento farmacológico , Convulsões/etiologia , Substância Branca/diagnóstico por imagem , Adulto Jovem
13.
JAMA Netw Open ; 4(2): e210112, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33630087

RESUMO

Importance: Genetic disorders are historically defined through phenotype-first approaches. However, risk estimates derived from phenotype-linked ascertainment may overestimate severity and penetrance. Pathogenic variants in DICER1 are associated with increased risks of rare and common neoplasms and thyroid disease in adults and children. This study explored how effectively a genome-first approach could characterize the clinical traits associated with germline DICER1 putative loss-of-function (pLOF) variants in an unselected clinical cohort. Objective: To examine the prevalence, penetrance, and phenotypic characteristics of carriers of germline DICER1 pLOF variants via genome-first ascertainment. Design, Setting, and Participants: This cohort study classifies DICER1 variants in germline exome sequence data from 92 296 participants of the Geisinger MyCode Community Health Initiative. Data for each MyCode participant were used from the start of the Geisinger electronic health record to February 1, 2018. Main Outcomes and Measures: Prevalence of germline DICER1 variation; penetrance of malignant tumors and thyroid disease in carriers of germline DICER1 variation; structured, manual review of electronic health records; and DICER1 sequencing of available tumors from an associated cancer registry. Results: A total of 92 296 adults (mean [SD] age, 59 [18] years; 98% white; 60% female) participated in the study. Germline DICER1 pLOF variants were observed in 1 in 3700 to 1 in 4600 participants, more than double the expected prevalence. Malignant tumors (primarily thyroid carcinoma) were observed in 4 of 25 participants (16%) with DICER1 pLOF variants, which is comparable (by 50 years of age) to the frequency of neoplasms in the largest registry- and clinic-based (phenotype-first) DICER1 studies published to date. DICER1 pLOF variants were significantly associated with risks of thyroidectomy (odds ratio [OR], 6.0; 95% CI, 2.2-16.3; P = .007) and thyroid cancer (OR, 9.2; 95% CI, 2.1-34.7; P = .02) compared with controls, but there was not a significant increase in the risk of goiter (OR, 1.8; 95% CI, 0.7-4.9). A female patient in her 80s who was a carrier of a germline DICER1 hotspot variant was apparently healthy on electronic health record review. The term DICER1 did not appear in any of the medical records of the 25 participants with a pLOF DICER1 variant, even in those affected with a known DICER1-associated tumor or thyroid phenotype. Conclusions and Relevance: This cohort study was able to ascertain individuals with germline DICER1 variants based on a genome-first approach rather than through a previously established DICER1-related phenotype. Use of the genome-first approach may complement more traditional approaches to syndrome delineation and may be an efficient approach for risk estimation.


Assuntos
RNA Helicases DEAD-box/genética , Penetrância , Fenótipo , Ribonuclease III/genética , Doenças da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Genoma , Mutação em Linhagem Germinativa , Bócio Nodular/epidemiologia , Bócio Nodular/genética , Doença de Graves/epidemiologia , Doença de Graves/genética , Heterozigoto , Humanos , Hipotireoidismo/epidemiologia , Hipotireoidismo/genética , Neoplasias Renais/epidemiologia , Neoplasias Renais/genética , Mutação com Perda de Função , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/genética , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Prevalência , Blastoma Pulmonar/epidemiologia , Blastoma Pulmonar/genética , Sarcoma/epidemiologia , Sarcoma/genética , Tumor de Células de Sertoli-Leydig/epidemiologia , Tumor de Células de Sertoli-Leydig/genética , Tumores do Estroma Gonadal e dos Cordões Sexuais/epidemiologia , Tumores do Estroma Gonadal e dos Cordões Sexuais/genética , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/genética , Doenças da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/epidemiologia , Nódulo da Glândula Tireoide/epidemiologia , Nódulo da Glândula Tireoide/genética , Tireoidectomia/estatística & dados numéricos , Tireotoxicose/epidemiologia , Tireotoxicose/genética , Tumor de Wilms/epidemiologia , Tumor de Wilms/genética , Adulto Jovem
15.
Mov Disord ; 36(6): 1381-1391, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33547842

RESUMO

BACKGROUND: The THAP1 gene encodes a transcription factor, and pathogenic variants cause a form of autosomal dominant, isolated dystonia (DYT-THAP1) with reduced penetrance. Factors underlying both reduced penetrance and the disease mechanism of DYT-THAP1 are largely unknown. METHODS: We performed transcriptome analysis on 29 cortical neuronal precursors derived from human-induced pluripotent stem cell lines generated from manifesting and nonmanifesting THAP1 mutation carriers and control individuals. RESULTS: Whole transcriptome analysis showed a penetrance-linked signature with expressional changes more pronounced in the group of manifesting (MMCs) than in nonmanifesting mutation carriers (NMCs) when compared to controls. A direct comparison of the transcriptomes in MMCs versus NMCs showed significant upregulation of the DRD4 gene in MMCs. A gene set enrichment analysis demonstrated alterations in various neurotransmitter release cycle pathways, extracellular matrix organization, and deoxyribonucleic acid methylation between MMCs and NMCs. When specifically considering transcription factors, the expression of YY1 and SIX2 differed in MMCs versus NMCs. Further, THAP1 was upregulated in the group of MMCs. CONCLUSIONS: To our knowledge, this is the first report systematically analyzing reduced penetrance in DYT-THAP1 in a human model using transcriptomes. Our findings indicate that transcriptional alterations during cortical development influence DYT-THAP1 pathogenesis and penetrance. We reinforce previously linked pathways including dopamine and eukaryotic translation initiation factor 2 alpha signaling in the pathogenesis of dystonia including DYT-THAP1 and suggest extracellular matrix organization and deoxyribonucleic acid methylation as mediators of disease protection. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Células-Tronco Pluripotentes Induzidas , Proteínas Reguladoras de Apoptose/genética , Proteínas de Ligação a DNA/genética , Humanos , Mutação/genética , Penetrância
16.
Invest Ophthalmol Vis Sci ; 62(1): 17, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33444430

RESUMO

Purpose: To characterize inheritance, penetrance, and trinucleotide repeat expansion stability in Fuchs endothelial corneal dystrophy (FECD). Methods: One thousand unrelated and related subjects with and without FECD were prospectively recruited. CTG18.1 repeat length (CTG18.1L) was determined via short tandem repeat assay and Southern blotting of leukocyte DNA. Multivariable logistic regression and generalized estimating equation models were employed. Results: There were 546 unrelated FECD cases (67.6% female; 70 ± 10 years) and 235 controls (63.8% female; 73 ± 8 years; all ≥ 50 years). CTG18.1 expansion (CTG18.1exp+) was observed in 424 (77.7%) cases and 18 (7.7%) controls (P = 2.48 × 10-44). CTG18.1 expansion was associated with FECD severity (P = 5.62 × 10-7). The family arm of the study included 331 members from 112 FECD-affected families; 87 families were CTG18.1exp+. Autosomal dominant inheritance with variable expression of FECD was observed, regardless of expansion status. FECD penetrance of CTG18.1 expansion increased with age, ranging from 44.4% in the youngest (19-46 years) to 86.2% in the oldest (64-91 years) age quartiles. Among 62 parent-offspring transmissions of CTG18.1exp+, 48 (77.4%) had a change in CTG18.1L ≤ 10 repeats, and eight (12.9%) were ≥50 repeats, including five large expansions (∼1000-2000 repeats) that contracted. Among 44 offspring who did not inherit the CTG18.1exp+ allele, eight (18.2%) exhibited FECD. Conclusions: CTG18.1 expansion was highly associated with FECD but demonstrated incomplete penetrance. CTG18.1L instability occurred in a minority of parent-offspring transmissions, with large expansions exhibiting contraction. The observation of FECD without CTG18.1 expansion among family members in CTG18.1exp+ families highlights the complexity of the relationship between the FECD phenotype and CTG18.1 expansion.


Assuntos
Distrofia Endotelial de Fuchs/genética , Fator de Transcrição 4/genética , Expansão das Repetições de Trinucleotídeos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Southern Blotting , DNA/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Padrões de Herança , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Linhagem , Penetrância , Reação em Cadeia da Polimerase , Polimorfismo Genético , Estudos Prospectivos , Adulto Jovem
17.
Hum Genet ; 140(5): 813-825, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33433679

RESUMO

Hirschsprung disease (HSCR) is a neurocristopathy characterized by the absence of enteric ganglia along variable lengths of the intestine. Genetic defects play a major role in HSCR pathogenesis with nearly 50% of patients having a structural or regulatory deficiency in the major susceptibility gene RET. However, complete molecular defects remain poorly characterized in most patients. Here, we performed detailed genetic, molecular, and populational investigations of rare null mutations and modifiers at the RET locus. We first verified the pathogenicity of three RET splice site mutants (c.1879 + 1G > A, c.2607 + 5G > A and c.2608-3C > G) at the RNA level. We also identified significantly higher risk allele (genotype) frequencies, and their over-transmission, from unaffected parents to affected offspring of three functionally independent enhancer variants (rs2506030, rs7069590 and rs2435357, with odd ratios (OR) of 2.09, 2.71 and 7.59, respectively, P < 0.001). These three common variants are in significant (P < 4.64 × 10-186) linkage disequilibrium in the Han Chinese population with ~ 60% of them carrying at least one copy and > 10% with two copies. We show that RET compound inheritance of rare and common variants prevails in 64% (seven out of 11) of Chinese HSCR families. This study supports the idea that common RET variants can modify the penetrance of rare null RET mutations in HSCR, and the combined high susceptibility allele dosage may constitute the unique raised "risk baseline" among the Chinese population.


Assuntos
Doença de Hirschsprung/genética , Intestinos/inervação , Penetrância , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas c-ret/genética , China , Feminino , Predisposição Genética para Doença/genética , Humanos , Lactente , Recém-Nascido , Desequilíbrio de Ligação/genética , Masculino , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA
18.
Hum Genet ; 140(6): 933-944, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33475861

RESUMO

Goldenhar syndrome or oculo-auriculo-vertebral spectrum (OAVS) is a complex developmental disorder characterized by asymmetric ear anomalies, hemifacial microsomia, ocular and vertebral defects. We aimed at identifying and characterizing a new gene associated with OAVS. Two affected brothers with OAVS were analyzed by exome sequencing that revealed a missense variant (p.(Asn358Ser)) in the EYA3 gene. EYA3 screening was then performed in 122 OAVS patients that identified the same variant in one individual from an unrelated family. Segregation assessment in both families showed incomplete penetrance and variable expressivity. We investigated this variant in cellular models to determine its pathogenicity and demonstrated an increased half-life of the mutated protein without impact on its ability to dephosphorylate H2AFX following DNA repair pathway induction. Proteomics performed on this cellular model revealed four significantly predicted upstream regulators which are PPARGC1B, YAP1, NFE2L2 and MYC. Moreover, eya3 knocked-down zebrafish embryos developed specific craniofacial abnormalities corroborating previous animal models and supporting its involvement in the OAVS. Additionally, EYA3 gene expression was deregulated in vitro by retinoic acid exposure. EYA3 is the second recurrent gene identified to be associated with OAVS. Moreover, based on protein interactions and related diseases, we suggest the DNA repair as a key molecular pathway involved in craniofacial development.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/genética , Síndrome de Goldenhar/genética , Mutação de Sentido Incorreto , Proteínas Tirosina Fosfatases/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Animais , Criança , Pré-Escolar , Proteínas de Ligação a DNA/deficiência , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica , Síndrome de Goldenhar/metabolismo , Síndrome de Goldenhar/patologia , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Linhagem , Penetrância , Proteínas Tirosina Fosfatases/deficiência , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Irmãos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequenciamento Completo do Exoma , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
19.
Am J Hum Genet ; 108(2): 337-345, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33434492

RESUMO

Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the Müllerian ducts (MD)/Wölffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Anormalidades Congênitas/genética , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/crescimento & desenvolvimento , Mutação , Ductos Mesonéfricos/crescimento & desenvolvimento , Adulto , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 7/genética , Códon sem Sentido , Feminino , Estudos de Associação Genética , Pleiotropia Genética , Proteínas Homeobox A10/genética , Proteínas de Homeodomínio/genética , Humanos , Fator de Transcrição PAX8/genética , Herança Paterna , Penetrância , Proteínas com Domínio T/genética , Fatores de Transcrição/genética , Proteínas Wnt/genética , Ductos Mesonéfricos/anormalidades
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