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1.
PLoS One ; 15(7): e0233582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735620

RESUMO

The craniofacial developmental disorder Burn-McKeown Syndrome (BMKS) is caused by biallelic variants in the pre-messenger RNA splicing factor gene TXNL4A/DIB1. The majority of affected individuals with BMKS have a 34 base pair deletion in the promoter region of one allele of TXNL4A combined with a loss-of-function variant on the other allele, resulting in reduced TXNL4A expression. However, it is unclear how reduced expression of this ubiquitously expressed spliceosome protein results in craniofacial defects during development. Here we reprogrammed peripheral mononuclear blood cells from a BMKS patient and her unaffected mother into induced pluripotent stem cells (iPSCs) and differentiated the iPSCs into induced neural crest cells (iNCCs), the key cell type required for correct craniofacial development. BMKS patient-derived iPSCs proliferated more slowly than both mother- and unrelated control-derived iPSCs, and RNA-Seq analysis revealed significant differences in gene expression and alternative splicing. Patient iPSCs displayed defective differentiation into iNCCs compared to maternal and unrelated control iPSCs, in particular a delay in undergoing an epithelial-to-mesenchymal transition (EMT). RNA-Seq analysis of differentiated iNCCs revealed widespread gene expression changes and mis-splicing in genes relevant to craniofacial and embryonic development that highlight a dampened response to WNT signalling, the key pathway activated during iNCC differentiation. Furthermore, we identified the mis-splicing of TCF7L2 exon 4, a key gene in the WNT pathway, as a potential cause of the downregulated WNT response in patient cells. Additionally, mis-spliced genes shared common sequence properties such as length, branch point to 3' splice site (BPS-3'SS) distance and splice site strengths, suggesting that splicing of particular subsets of genes is particularly sensitive to changes in TXNL4A expression. Together, these data provide the first insight into how reduced TXNL4A expression in BMKS patients might compromise splicing and NCC function, resulting in defective craniofacial development in the embryo.


Assuntos
Processamento Alternativo , Atresia das Cóanas/patologia , Surdez/congênito , Regulação da Expressão Gênica no Desenvolvimento , Cardiopatias Congênitas/patologia , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Ribonucleoproteína Nuclear Pequena U5/deficiência , Spliceossomos/fisiologia , Apoptose , Diferenciação Celular , Técnicas de Reprogramação Celular , Atresia das Cóanas/genética , Células Clonais , Surdez/genética , Surdez/patologia , Transição Epitelial-Mesenquimal , Éxons/genética , Face/embriologia , Facies , Feminino , Cabeça/embriologia , Cardiopatias Congênitas/genética , Humanos , Crista Neural/citologia , Regiões Promotoras Genéticas/genética , Sítios de Splice de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonucleoproteína Nuclear Pequena U5/genética , Deleção de Sequência , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Via de Sinalização Wnt
2.
Int Heart J ; 61(4): 761-768, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32641638

RESUMO

Congenital heart defect (CHD) represents the most common birth deformity, afflicting 1% of all births worldwide, and accounts for substantial morbidity and mortality. Increasing evidence highlights the pivotal roles of genetic etiologies in the pathogenesis of CHD, and pathogenic mutations in multiple genes, including TBX5 encoding a cardiac core transcription factor key to cardiovascular morphogenesis, have been involved in CHD. However, due to pronounced genetic heterogeneity of CHD, the genetic determinants underlying CHD in most cases remain obscure. In this investigation, by sequencing analysis of the coding exons and flanking introns of the TBX5 gene in 198 unrelated patients affected with CHD, a novel heterozygous mutation, NM_000192.3: c.692C>T; p. (Pro231Leu), was identified in an index patient with familial double outlet right ventricle (DORV), ventricular septal defect (VSD), and atrioventricular block (AVB). Genetic analysis of the proband's pedigree showed that the mutation co-segregated with the diseases. The missense mutation, which altered the amino acid conserved evolutionarily, was absent from 266 unrelated healthy subjects. Functional analyses with a dual-luciferase reporter assay system unveiled that the Pro231Leu-mutant TBX5 was associated with significantly reduced transcriptional activity on its target genes MYH6 and NPPA. Furthermore, the mutation disrupted the synergistic transactivation between TBX5 and NKX2-5 as well as GATA4, two other transcription factors causally linked to CHD. This study firstly links TBX5 loss-of-function mutation to familial DORV, VSD, and AVB, which provides novel insight into the mechanism underpinning CHD and AVB, suggesting potential implications for genetic evaluation and individualized treatment of patients affected by CHD and AVB.


Assuntos
Bloqueio Atrioventricular/genética , Cardiopatias Congênitas/genética , Proteínas com Domínio T/genética , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Bovinos , Criança , Pré-Escolar , Cães , Feminino , Humanos , Lactente , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Ratos , Adulto Jovem
3.
Medicine (Baltimore) ; 99(29): e20574, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32702813

RESUMO

RATIONALE: Schaaf-Yang syndrome, a rare imprinted hereditary disease caused by MAGEL2 variants, manifests as developmental delay/intellectual disability, neonatal hypotonia, feeding difficulties, contractures, and autism spectrum disorder. PATIENT CONCERNS: Patient 1 and 2 were infant girls presenting facial dysmorphisms, contractures of interphalangeal joints, neonatal hypotonia, feeding difficulties, congenital heart diseases, and respiratory complications. Besides, Patient 2 presented with delayed psychomotor development. DIAGNOSIS: Whole-exome sequencing was performed and heterozygous mutations of the MAGEL2 gene were detected in the patients. They were diagnosed as Schaaf-Yang syndrome. INTERVENTIONS: The patients received supportive treatment including mechanical ventilation, parenteral nutrition and gastric tube feeding. OUTCOMES: Whole-exome sequencing revealed de novo heterozygous c.1996dupC pathogenic mutations in the MAGEL2 gene in the 2 patients. They died due to respiratory failure at the age of 20 days and 98 days, respectively. LESSONS: Our results indicate that MAGEL2 variants can cause congenital heart disease and fatal respiratory complications, broadening the phenotypic spectrum and adding to the fatal cases of Schaaf-Yang syndrome. We highly suggest that the MAGEL2 gene should be added to gene-panels or gene-filters in next-generation sequencing-based diagnostics, which is of great significance for early diagnosis and early intervention of Schaaf-Yang syndrome patients.


Assuntos
Anormalidades Múltiplas/genética , Testes Genéticos/métodos , Proteínas/genética , Sequenciamento Completo do Exoma/métodos , Criança , Contratura/genética , Anormalidades Craniofaciais/genética , Deficiências do Desenvolvimento/genética , Evolução Fatal , Transtornos da Alimentação e da Ingestão de Alimentos/genética , Feminino , Articulações dos Dedos/fisiopatologia , Cardiopatias Congênitas/genética , Humanos , Lactente , Recém-Nascido , Masculino , Hipotonia Muscular/genética , Atrofia Muscular/genética , Cuidados Paliativos , Insuficiência Respiratória/genética , Síndrome
4.
Medicine (Baltimore) ; 99(27): e19868, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629623

RESUMO

The purpose of this study was to investigate the relationship between glioma-associated oncogene homolog 1 (GLI1) rs2228226 and rs10783826 polymorphisms and congenital heart disease (CHD) risk in a Chinese Han population.Genotyping for our interested polymorphisms was performed using polymerase chain reaction-restriction fragment length polymorphism in 106 CHD patients and 112 healthy controls. Hardy-Weinberg equilibrium status in the control group was also checked via χ test. Differences in genotype and allele frequencies between the case and control groups were analyzed adopting Chi-Squared test as well, and the relative risk of CHD resulting from GLI1 genetic variants was checked via calculating odds ratio (OR) and 95% confidence interval (95%CI).CC genotype of rs2228226 showed significantly higher frequency in CHD patients than in controls (P = .011), indicating that it increased the disease risk (OR = 3.257, 95%CI = 1.280-8.287). Similarly, C allele of the polymorphism elevated CHD incidence by 1.609 folds, compared with G allele (OR = 1.609, 95%CI = 1.089-2.376). However, rs10783826 was not correlated with the occurrence of CHD.GLI1 rs2228226 polymorphism may be a risk factor for CHD in Chinese Han population, but not rs10783826.


Assuntos
Cardiopatias Congênitas/genética , Proteína GLI1 em Dedos de Zinco/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Polimorfismo de Nucleotídeo Único
5.
Medicine (Baltimore) ; 99(26): e20400, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590727

RESUMO

This study aimed to explore the combined association between AKT serine/threonine kinase 1 (AKT1) polymorphisms and congenital heart disease (CHD) risk, meanwhile, the role of AKT1 single polymorphism on CHD was also analyzed.In the first, AKT1 polymorphisms were genotyped in 130 CHD patients and 145 healthy people with the way of polymerase chain reaction-direct sequencing. The clinical data and genotypes, alleles between 2 groups were compared by χ test and the genotype distributions in the control group were checked by Hardy-Weinberg equilibrium. The relative risk strength of disease based on genetic variant was revealed using odds ratio (OR) with 95% confidence interval (95%CI).In 3 polymorphisms of AKT1 (rs1130214, rs2494732, rs3803300), the GT/TT genotype of rs1130214 in cases and controls had a significant frequency difference (P = .04) and was 1.71 times risk developing CHD, compared with AA (OR = 1.71, 95%CI = 1.02-2.86), and T allele had 1.63 times risk for carriers (OR = 1.63, 95%CI = 1.05-2.54). Similarly, both rs3803300 GG genotype and G allele had obvious differences between case and control groups (P < .05) and it was closely associated with CHD susceptibility. At the same time, the combined effects of rs1130214, rs3803300 and family history, smoking were found in our study.AKT1 rs1130214, rs3803300 polymorphisms are associated with the increased susceptibility to CHD. Environmental factors are found the interaction with AKT1 polymorphisms. Further study is needed to verify this conclusion.


Assuntos
Cardiopatias Congênitas/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-akt/genética , Fumar/efeitos adversos , Adolescente , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , China , Feminino , Predisposição Genética para Doença , Genótipo , Heterozigoto , Humanos , Masculino
6.
PLoS One ; 15(6): e0233007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492036

RESUMO

BACKGROUND: In humans, stillbirth describes the death of a fetus before birth after 28 weeks gestation, and accounts for approximately 2.6 million deaths worldwide annually. In high-income countries, up to half of stillbirths have an unknown cause and are described as "unexplained stillbirths"; this lack of understanding impairs efforts to prevent stillbirth. There are also few animal models of stillbirth, but those that have been described usually have significant placental abnormalities. This study describes a novel mutant murine model of fetal death with atrial conduction block due to an ErbB2 missense mutation which is not associated with abnormal placental morphology. METHODS: Phenotypic characterisation and histological analysis of the mutant mouse model was conducted. The mRNA distribution of the early cardiomyocyte marker Nkx2-5 was assessed via in situ hybridisation. Cardiac structure was quantified and cellular morphology evaluated by electron microscopy. Immunostaining was employed to quantify placental structure and cell characteristics on matched heterozygous and homozygous mutant placental samples. RESULTS: There were no structural abnormalities observed in hearts of mutant embryos. Comparable Nkx2-5 expression was observed in hearts of mutants and controls, suggesting normal cardiac specification. Additionally, there was no significant difference in the weight, placenta dimensions, giant cell characteristics, labyrinth tissue composition, levels of apoptosis, proliferation or vascularisation between placentas of homozygous mutant mice and controls. CONCLUSION: Embryonic lethality in the ErbB2 homozygous mutant mouse cannot be attributed to placental pathology. As such, we conclude the ErbB2M802R mutant is a model of stillbirth with a non-placental cause of death. The mechanism of the atrial block resulting from ErbB2 mutation and its role in embryonic death is still unclear. Studying this mutant mouse model could identify candidate genes involved in stillbirth associated with structural or functional cardiac defects.


Assuntos
Cardiopatias Congênitas/genética , Mutação de Sentido Incorreto , Receptor ErbB-2/genética , Natimorto/genética , Animais , Modelos Animais de Doenças , Feminino , Bloqueio Cardíaco/congênito , Bloqueio Cardíaco/genética , Bloqueio Cardíaco/metabolismo , Bloqueio Cardíaco/patologia , Cardiopatias Congênitas/metabolismo , Cardiopatias Congênitas/patologia , Heterozigoto , Proteína Homeobox Nkx-2.5/genética , Homozigoto , Humanos , Camundongos , Camundongos Mutantes , Miocárdio/metabolismo , Miocárdio/patologia , Placenta/anormalidades , Placenta/patologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
7.
PLoS One ; 15(6): e0234357, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32516339

RESUMO

Congenital heart defects (CHDs) affect approximately 1% of newborns. Epidemiological studies have identified several genetically-mediated maternal phenotypes (e.g., pregestational diabetes, chronic hypertension) that are associated with the risk of CHDs in offspring. However, the role of the maternal genome in determining CHD risk has not been defined. We present findings from gene-level, genome-wide studies that link CHDs to maternal effect genes as well as to maternal genes related to hypertension and proteostasis. Maternal effect genes, which provide the mRNAs and proteins in the oocyte that guide early embryonic development before zygotic gene activation, have not previously been implicated in CHD risk. Our findings support a role for and suggest new pathways by which the maternal genome may contribute to the development of CHDs in offspring.


Assuntos
Cardiopatias Congênitas/genética , Herança Materna/genética , Adulto , Estudos de Casos e Controles , Pré-Escolar , Família , Feminino , Testes Genéticos/métodos , Cardiopatias Congênitas/etiologia , Humanos , Hipertensão/genética , Lactente , Recém-Nascido , Masculino , Exposição Materna/efeitos adversos , Pessoa de Meia-Idade , Oócitos/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Proteostase/genética , Fatores de Risco
8.
Eur. j. anat ; 24(3): 211-220, mayo 2020. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-191470

RESUMO

Cardiac malformations are very prevalent and can be caused both by defective genes and envi-ronmental teratogens. Among the latter, caffeine causes malformations when exposed during early cardiac development, whereas its later effects are still unclear. We exposed three-day incubated (D3) chick embryos to 2 mg caffeine and analyzed them at D5, D7 and D9. The embryos were serially sec-tioned and analyzed two-dimensionally. Alternatively, the sections of D9 embryos were reconstructed three-dimensionally using Amira® software and analyzed volumetrically. The expres-sion of genes involved in endothelial-mesenchymal transformation (EMT) was studied by real-time PCR. Interestingly, caffeine treatment at D3 em-bryos did not induce cardiac malformations, but did delay growth, in particular that of the ventricles and ventricular trabeculae. Furthermore, it affected EMT in the endocardial cushion and atrioventricu-lar valves. Gene-expression analysis revealed that caffeine had a progressively deleterious effect on the expressions of GATA4, MMP2, SNAIL1, TWIST1, and VIMENTIN. The effect of late caf-feine administration on the chicken embryos would provide suggestive evident towards a possible heart developmental defect in humans, particularly heavy caffeine consumers during pregnancy


No disponible


Assuntos
Animais , Embrião de Galinha/efeitos dos fármacos , Cafeína/administração & dosagem , Cardiopatias Congênitas/induzido quimicamente , Cardiopatias Congênitas/genética , Embrião de Galinha/anatomia & histologia , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Análise de Dados , Titulometria/métodos , Ecocardiografia Tridimensional , Anatomia Transversal
9.
Chemosphere ; 251: 126610, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443250

RESUMO

Trichloroethylene (TCE), a widely used organic solvent, is a common environmental pollutant. Increasing evidence indicates that maternal TCE exposure is associated with congenital cardiac defects, but the underlining mechanisms remain largely unknown. In this study, we revealed that TCE exposure significantly induced heart defects and dysfunctions in zebrafish embryos. Heart tissues were dissected and subjected to high throughput sequencing and qPCR to identify differentially expressed miRNAs and mRNAs. The effects of miRNA were further verified by microinjection of antagomir or agomir. Reactive Oxygen Species (ROS) and cell proliferation were measured by using dichlorodihydrofluorescein diacetate (DCFH-DA) and EdU staining, respectively. Our results showed that 19 miRNAs were downregulated whereas 48 miRNAs were upregulated in the heart of zebrafish embryos. The downregulation of miR-133a and the upregulation of miR-182 were further validated. Moreover, we found that miR-133a agomir significantly alleviated the TCE-induced heart defects while miR-133a antagomir mimicked the toxic effect of TCE on heart development. Furthermore, miR-133a agomir significantly counteracted TCE-induced ROS production and excessive cell proliferation in the heart of zebrafish embryos. In conclusion, our results indicate that miR-133a mediates TCE-induced ROS generation, leading to excessive cell proliferation and heart defects.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Cardiopatias Congênitas/induzido quimicamente , Coração/efeitos dos fármacos , MicroRNAs/genética , Tricloroetileno/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Cardiotoxicidade , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação para Baixo , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Coração/embriologia , Cardiopatias Congênitas/genética , Regulação para Cima
10.
BMC Med Genet ; 21(1): 95, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380971

RESUMO

BACKGROUND: Conotruncal heart defects (CTDs) are a group of congenital heart malformations that cause anomalies of cardiac outflow tracts. In the past few decades, many genes related to CTDs have been reported. Serum response factor (SRF) is a ubiquitous nuclear protein that acts as transcription factor, and SRF was found to be a critical factor in heart development and to be strongly expressed in the myocardium of the developing mouse and chicken hearts. The targeted inactivation of SRF during heart development leads to embryonic lethality and myocardial defects in mice. METHODS: To illustrate the relationship between SRF and human heart defects, we screened SRF mutations in 527 CTD patients, a cross sectional study. DNA was extracted from peripheral leukocyte cells for target sequencing. The mutations of SRF were detected and validated by Sanger sequencing. The affection of the mutations on wild-type protein was analyzed by in silico softwares. Western blot and real time PCR were used to analyze the changes of the expression of the mutant mRNA and protein. In addition, we carried out dual luciferase reporter assay to explore the transcriptional activity of the mutant SRF. RESULTS: Among the target sequencing results of 527 patients, two novel mutations (Mut1: c.821A > G p.G274D, the adenine(A) was mutated to guanine(G) at position 821 of the SRF gene coding sequences (CDS), lead to the Glycine(G) mutated to Asparticacid(D) at position 274 of the SRF protein amino acid sequences; Mut2: c.880G > T p.G294C, the guanine(G) was mutated to thymine (T) at position 880 of the SRF CDS, lead to the Glycine(G) mutated to Cysteine (C) at position 294 of the SRF protein amino acid sequences.) of SRF (NM_003131.4) were identified. Western blotting and real-time PCR showed that there were no obvious differences between the protein expression and mRNA transcription of mutants and wild-type SRF. A dual luciferase reporter assay showed that both SRF mutants (G274D and G294C) impaired SRF transcriptional activity at the SRF promoter and atrial natriuretic factor (ANF) promoter (p < 0.05), additionally, the mutants displayed reduced synergism with GATA4. CONCLUSION: These results suggest that SRF-p.G274D and SRF-p.G294C may have potential pathogenic effects.


Assuntos
Fator Natriurético Atrial/genética , Fator de Transcrição GATA4/genética , Cardiopatias Congênitas/genética , Fator de Resposta Sérica/genética , Sequência de Aminoácidos/genética , Animais , Estudos Transversais , Feminino , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Cardiopatias Congênitas/patologia , Proteínas de Homeodomínio/genética , Humanos , Masculino , Camundongos , Mutação de Sentido Incorreto/genética , Miocárdio/metabolismo , Miocárdio/patologia , Regiões Promotoras Genéticas/genética
11.
Int Heart J ; 61(3): 553-561, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32418960

RESUMO

Many published studies have evaluated the association between the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133) polymorphism and the risk of congenital heart disease (CHD); however, the specific conclusion is still controversial.To get a more accurate conclusion, we used a meta-analysis to evaluate the association between the MTHFR gene C677T polymorphism and the risk of CHD.Based on the design-based search strategy, a comprehensive literature search was conducted on PubMed, OVID, Cochrane Library, Embase, Wanfang, CNKI, and Web of Science. We selected the Newcastle-Ottawa Scale (NOS) to assess the quality of the included studies. We performed a heterogeneity test on the results of the study and calculated the combined odds ratios (ORs) and its corresponding 95% confidence intervals (95% CIs) under a random- or fixed-effect model. Subgroup analyses were conducted by ethnicity, source of controls, sample size, and genotyping method. Sensitivity analysis was used to insure authenticity of this meta-analysis result. Egger's test and Begg's funnel plot were performed to detect publication bias.Eventually, our meta-analysis included 15 eligible studies. We observed a significant correlation between the MTHFR C677T polymorphism and the development of CHD in the recessive model (OR: 1.35, 95% CI: 1.06-1.71, P = 0.006) for the overall population. In subgroups stratified by ethnicity and source of controls, subgroup analyses indicated similar associations in Asians and hospital-based groups, but not for Caucasians and population-based groups. Egger's test and Begg's funnel plot demonstrated no significant publication bias in our study.Our analysis identified that MTHFR C677T allele is a risk genetic for CHD development, especially in Asians compared with Caucasians.


Assuntos
Cardiopatias Congênitas/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Predisposição Genética para Doença , Humanos
12.
Tunis Med ; 98(2): 161-163, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32395807

RESUMO

We report the case of a 23-year-old woman with a not yet described (to the best of our knowledge) association of left ventricle non-compaction with both atrial and ventricular defects. Family genetic survey concluded to, a probably sporadic, E101K gene mutation.


Assuntos
Cardiopatias Congênitas/diagnóstico , Comunicação Interatrial/diagnóstico , Ventrículos do Coração/anormalidades , Substituição de Aminoácidos/genética , Proteínas Associadas à Distrofina/genética , Feminino , Ácido Glutâmico/genética , Cardiopatias Congênitas/genética , Comunicação Interatrial/complicações , Comunicação Interatrial/genética , Humanos , Lisina/genética , Mutação de Sentido Incorreto , Neuropeptídeos/genética , Adulto Jovem
13.
Adv Exp Med Biol ; 1236: 189-223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32304074

RESUMO

Congenital heart defects (CHDs) are among the most common human birth defects. However, the etiology of a large proportion of CHDs remains undefined. Studies identifying the molecular and cellular mechanisms that underlie cardiac development have been critical to elucidating the origin of CHDs. Building upon this knowledge to understand the pathogenesis of CHDs requires examining how genetic or environmental stress changes normal cardiac development. Due to strong molecular conservation to humans and unique technical advantages, studies using zebrafish have elucidated both fundamental principles of cardiac development and have been used to create cardiac disease models. In this chapter we examine the unique toolset available to zebrafish researchers and how those tools are used to interrogate the genetic and environmental contributions to CHDs.


Assuntos
Meio Ambiente , Cardiopatias Congênitas/etiologia , Cardiopatias Congênitas/genética , Peixe-Zebra/genética , Animais , Interação Gene-Ambiente , Coração/embriologia , Cardiopatias Congênitas/embriologia , Cardiopatias Congênitas/patologia , Humanos , Peixe-Zebra/embriologia
14.
BMC Med Genet ; 21(1): 70, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245430

RESUMO

BACKGROUND: Mutations in GATA6 are the most frequent cause of pancreatic agenesis. Most cases present with neonatal diabetes mellitus. CASE PRESENTATION: The case was a female born after an uncomplicated pregnancy and delivery in a non-consanguineous family (3.59 kg, 70th percentile). Severe cardiac malformations were diagnosed at two and a half months old. No hyperglycaemic episodes were recorded in the neonatal period. Diabetes was diagnosed at 21 years due to the detection of incidental glycosuria. She had a low but detectable C-peptide level at diagnosis. Anti-GAD and Islet-cell antibodies were negative and she failed oral hypoglycaemic therapy and was started on insulin. Abdominal MRI revealed the absence of most of the neck, body, and tail of pancreas with normal pancreas elastase levels. Criteria for type 1 or type 2 diabetes were not fulfilled, therefore a next generation sequencing (NGS) panel was performed. A novel heterozygous pathogenic GATA6 mutation (p.Tyr235Ter) was identified. The GATA6 variant was not detected in her parents, implying that the mutation had arisen de novo in the proband. CONCLUSION: Rarely GATA6 mutations can cause adult onset diabetes. This report highlights the importance of screening the GATA6 gene in patients with adult-onset diabetes, congenital cardiac defects and pancreatic agenesis with no first-degree family history of diabetes. It also emphasizes the importance of genetic counselling in these patients as future offspring will be at risk of inheriting the variant and developing GATA6 anomalies.


Assuntos
Anormalidades Múltiplas/genética , Diabetes Mellitus Tipo 2/genética , Fator de Transcrição GATA6/genética , Cardiopatias Congênitas/genética , Mutação , Pâncreas/anormalidades , Adulto , Diabetes Mellitus Tipo 2/complicações , Feminino , Cardiopatias Congênitas/complicações , Humanos , Lactente , Recém-Nascido , Transtornos de Início Tardio , Linhagem , Adulto Jovem
15.
BMC Med Genet ; 21(1): 78, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293321

RESUMO

BACKGROUND: The protein Kruppel-like factor 13 (KLF13) is a member of the KLF family and has been identified as a cardiac transcription factor that is involved in heart development. However, the relationship between KLF13 variants and CHDs in humans remains largely unknown. The present study aimed to screen the KLF13 variants in CHD patients and genetically analyze the functions of these variants. METHODS: KLF13 variants were sequenced in a cohort of 309 CHD patients and population-matched healthy controls (n = 200) using targeted sequencing. To investigate the effect of variants on the functional properties of the KLF13 protein, the expression and subcellular localization of the protein, as well as the transcriptional activities of downstream genes and physical interactions with other transcription factors, were assessed. RESULTS: Two heterozygous variants, c.487C > T (P163S) and c.467G > A (S156N), were identified in two out of 309 CHD patients with tricuspid valve atresia and transposition of the great arteries, respectively. No variants were found among healthy controls. The variant c.467G > A (S156N) had increased protein expression and enhanced functionality compared with the wild type, without affecting the subcellular localization. The other variant, c.487C > T (P163S), did not show any abnormalities in protein expression or subcellular localization; however, it inhibited the transcriptional activities of downstream target genes and physically interacted with TBX5, another cardiac transcription factor. CONCLUSION: Our results show that the S156N and P163S variants may affect the transcriptional function of KLF13 and physical interaction with TBX5. These results identified KLF13 as a potential genetic risk factor for congenital heart disease.


Assuntos
Proteínas de Ciclo Celular/genética , Cardiopatias Congênitas/genética , Fatores de Transcrição Kruppel-Like/genética , Proteínas Repressoras/genética , Proteínas com Domínio T/genética , Atresia Tricúspide/genética , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica/genética , Coração/fisiopatologia , Cardiopatias Congênitas/fisiopatologia , Heterozigoto , Humanos , Lactente , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único/genética , Transposição dos Grandes Vasos/metabolismo , Transposição dos Grandes Vasos/fisiopatologia , Atresia Tricúspide/fisiopatologia
16.
PLoS Genet ; 16(4): e1008739, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32320395

RESUMO

Inositol 1,4,5-trisphosphate receptors (IP3Rs) are a family of intracellular Ca2+ release channels located on the ER membrane, which in mammals consist of 3 different subtypes (IP3R1, IP3R2, and IP3R3) encoded by 3 genes, Itpr1, Itpr2, and Itpr3, respectively. Studies utilizing genetic knockout mouse models have demonstrated that IP3Rs are essential for embryonic survival in a redundant manner. Deletion of both IP3R1 and IP3R2 has been shown to cause cardiovascular defects and embryonic lethality. However, it remains unknown which cell types account for the cardiovascular defects in IP3R1 and IP3R2 double knockout (DKO) mice. In this study, we generated conditional IP3R1 and IP3R2 knockout mouse models with both genes deleted in specific cardiovascular cell lineages. Our results revealed that deletion of IP3R1 and IP3R2 in cardiomyocytes by TnT-Cre, in endothelial / hematopoietic cells by Tie2-Cre and Flk1-Cre, or in early precursors of the cardiovascular lineages by Mesp1-Cre, resulted in no phenotypes. This demonstrated that deletion of both IP3R genes in cardiovascular cell lineages cannot account for the cardiovascular defects and embryonic lethality observed in DKO mice. We then revisited and performed more detailed phenotypic analysis in DKO embryos, and found that DKO embryos developed cardiovascular defects including reduced size of aortas, enlarged cardiac chambers, as well as growth retardation at embryonic day (E) 9.5, but in varied degrees of severity. Interestingly, we also observed allantoic-placental defects including reduced sizes of umbilical vessels and reduced depth of placental labyrinth in DKO embryos, which could occur independently from other phenotypes in DKO embryos even without obvious growth retardation. Furthermore, deletion of both IP3R1 and IP3R2 by the epiblast-specific Meox2-Cre, which targets all the fetal tissues and extraembryonic mesoderm but not extraembryonic trophoblast cells, also resulted in embryonic lethality and similar allantoic-placental defects. Taken together, our results demonstrated that IP3R1 and IP3R2 play an essential and redundant role in maintaining the integrity of fetal-maternal connection and embryonic viability.


Assuntos
Retardo do Crescimento Fetal/genética , Coração Fetal/metabolismo , Cardiopatias Congênitas/genética , Receptores de Inositol 1,4,5-Trifosfato/genética , Placenta/metabolismo , Animais , Células Progenitoras Endoteliais/metabolismo , Feminino , Coração Fetal/embriologia , Deleção de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Placenta/embriologia , Gravidez
17.
Am J Hum Genet ; 106(5): 623-631, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32275884

RESUMO

Nucleoporins (NUPs) are an essential component of the nuclear-pore complex, which regulates nucleocytoplasmic transport of macromolecules. Pathogenic variants in NUP genes have been linked to several inherited human diseases, including a number with progressive neurological degeneration. We present six affected individuals with bi-allelic truncating variants in NUP188 and strikingly similar phenotypes and clinical courses, representing a recognizable genetic syndrome; the individuals are from four unrelated families. Key clinical features include congenital cataracts, hypotonia, prenatal-onset ventriculomegaly, white-matter abnormalities, hypoplastic corpus callosum, congenital heart defects, and central hypoventilation. Characteristic dysmorphic features include small palpebral fissures, a wide nasal bridge and nose, micrognathia, and digital anomalies. All affected individuals died as a result of respiratory failure, and five of them died within the first year of life. Nuclear import of proteins was decreased in affected individuals' fibroblasts, supporting a possible disease mechanism. CRISPR-mediated knockout of NUP188 in Drosophila revealed motor deficits and seizure susceptibility, partially recapitulating the neurological phenotype seen in affected individuals. Removal of NUP188 also resulted in aberrant dendrite tiling, suggesting a potential role of NUP188 in dendritic development. Two of the NUP188 pathogenic variants are enriched in the Ashkenazi Jewish population in gnomAD, a finding we confirmed with a separate targeted population screen of an international sampling of 3,225 healthy Ashkenazi Jewish individuals. Taken together, our results implicate bi-allelic loss-of-function NUP188 variants in a recessive syndrome characterized by a distinct neurologic, ophthalmologic, and facial phenotype.


Assuntos
Alelos , Encéfalo/anormalidades , Proteínas de Drosophila/genética , Anormalidades do Olho/genética , Cardiopatias Congênitas/genética , Mutação com Perda de Função/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/metabolismo , Pré-Escolar , Dendritos/metabolismo , Dendritos/patologia , Drosophila melanogaster , Anormalidades do Olho/mortalidade , Feminino , Fibroblastos , Genes Recessivos , Cardiopatias Congênitas/mortalidade , Humanos , Lactente , Recém-Nascido , Judeus/genética , Masculino , Complexo de Proteínas Formadoras de Poros Nucleares/deficiência , Convulsões/metabolismo , Síndrome , beta Carioferinas/metabolismo
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(5): 555-558, 2020 May 10.
Artigo em Chinês | MEDLINE | ID: mdl-32335885

RESUMO

OBJECTIVE: To explore the genetic basis for an infant with multiple malformations including congenital heart disease and cleft palate. METHODS: The child and his parents were subjected to conventional chromosomal karyotyping and low-coverage massively parallel copy number variation sequencing (CNV-seq) analysis. RESULTS: The infant was found to have a 46,X,add(Y)(q11.23) karyotype, and his CNV-seq result was seq [hg19] 22q12.1q13.3 (29 520 001-51 180 000)× 3. His parents were found to be normal by both methods. CONCLUSION: The additional chromosomal material found on Yq, verified as duplication of 22q12.1-q13.3, may account for the abnormal phenotype in this infant. CNV-seq has provided a useful complement for the diagnosis and more accurate information for genetic counseling.


Assuntos
Anormalidades Múltiplas , Duplicação Cromossômica , Cromossomos Humanos Par 22 , Anormalidades Múltiplas/genética , Criança , Cromossomos Humanos Par 22/genética , Fissura Palatina/genética , Variações do Número de Cópias de DNA , Testes Genéticos , Cardiopatias Congênitas/genética , Humanos , Lactente , Cariotipagem
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(5): 567-569, 2020 May 10.
Artigo em Chinês | MEDLINE | ID: mdl-32335888

RESUMO

OBJECTIVE: To explore the genotype-phenotype correlation of Cardio-facio-cutaneous syndrome (CFCS) caused by MAP2K1 gene variants. METHODS: Genomic DNA was extracted from peripheral blood sample from a child patient and his parents. Whole exome sequencing (WES) was carried out for the patient. Suspected variant was verified by Sanger sequencing. RESULTS: The patient was a 1-year-8-month old Chinese male who manifested short stature, psychomotor retardation, relative macrocephaly, distinctive facial features, and congenital heart disease. WES test revealed a heterozygous missense c.389A>G (p.Tyr130Cys) variant in the MAP2K1 gene. Sanger sequencing has confirmed the variant as de novo. According to ACMG/AMP guidelines, the variant was classified as pathogenic. CONCLUSION: Compared with previously reported CFCS cases due to MAP2K1 variants. The patient showed obvious behavioral problems, good appetite and tricuspid regurgitation, which may to be novel features for CFCS.


Assuntos
Displasia Ectodérmica , Facies , Insuficiência de Crescimento , Variação Genética , Cardiopatias Congênitas , MAP Quinase Quinase 1 , China , Displasia Ectodérmica/genética , Insuficiência de Crescimento/genética , Estudos de Associação Genética , Cardiopatias Congênitas/genética , Heterozigoto , Humanos , Lactente , MAP Quinase Quinase 1/genética , Masculino , Mutação , Sequenciamento Completo do Exoma
20.
BMC Med Genet ; 21(1): 50, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164556

RESUMO

BACKGROUND: Noonan syndrome (NS), an autosomal dominant developmental genetic disorder, is caused by germline mutations in genes associated with the RAS / mitogen-activated protein kinase (MAPK) pathway. In several studies PTPN11 is one of the genes with a significant number of pathogenic variants in NS-affected patients. Therefore, clinically diagnosed NS individuals are initially tested for pathogenic variants in PTPN11 gene to confirm the relationship before studying genotype-phenotype correlation. METHODS: Individuals (363) with clinically diagnosed NS from four hospitals in South India were recruited and the exons of PTPN11 gene were sequenced. RESULTS: Thirty-two previously described pathogenic variants in eight different exons in PTPN11 gene were detected in 107 patients, of whom 10 were familial cases. Exons 3, 8 and 13 had the highest number of pathogenic variants. The most commonly identified pathogenic variants in this series were in exon 8 (c.922A > G, c.923A > G), observed in 22 of the affected. Congenital cardiac anomalies were present in 84% of the mutation-positive cohort, the majority being defects in the right side of the heart. The most common facial features were downward-slanting palpebral fissures, hypertelorism and low-set posteriorly rotated ears. Other clinical features included short stature (40%), pectus excavatum (54%) and, in males, unilateral or bilateral cryptorchidism (44%). CONCLUSION: The clinical features and mutational spectrum observed in our cohort are similar to those reported in other large studies done worldwide. This is the largest case series of NS-affected individuals with PTPN11 mutations described till date from India.


Assuntos
Síndrome de Noonan/genética , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Análise Mutacional de DNA , Família , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/genética , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Masculino , Síndrome de Noonan/epidemiologia , Fenótipo , Adulto Jovem
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