RESUMO
Prenatal alcohol exposure is the foremost preventable etiology of intellectual disability and leads to a collection of diagnoses known as Fetal Alcohol Spectrum Disorders (FASD). Alcohol (EtOH) impacts diverse neural cell types and activity, but the precise functional pathophysiological effects on the human fetal cerebral cortex are unclear. Here, we used human cortical organoids to study the effects of EtOH on neurogenesis and validated our findings in primary human fetal neurons. EtOH exposure produced temporally dependent cellular effects on proliferation, cell cycle, and apoptosis. In addition, we identified EtOH-induced alterations in post-translational histone modifications and chromatin accessibility, leading to impairment of cAMP and calcium signaling, glutamatergic synaptic development, and astrocytic function. Proteomic spatial profiling of cortical organoids showed region-specific, EtOH-induced alterations linked to changes in cytoskeleton, gliogenesis, and impaired synaptogenesis. Finally, multi-electrode array electrophysiology recordings confirmed the deleterious impact of EtOH on neural network formation and activity in cortical organoids, which was validated in primary human fetal tissues. Our findings demonstrate progress in defining the human molecular and cellular phenotypic signatures of prenatal alcohol exposure on functional neurodevelopment, increasing our knowledge for potential therapeutic interventions targeting FASD symptoms.
Assuntos
Córtex Cerebral , Etanol , Vias Neurais , Neurogênese , Neurônios , Organoides , Feminino , Humanos , Masculino , Gravidez , Astrócitos/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/genética , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Etanol/farmacologia , Transtornos do Espectro Alcoólico Fetal/etiologia , Transtornos do Espectro Alcoólico Fetal/genética , Feto/citologia , Perfilação da Expressão Gênica , Rede Nervosa/efeitos dos fármacos , Transtornos do Neurodesenvolvimento/induzido quimicamente , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Organoides/citologia , Organoides/efeitos dos fármacos , Organoides/patologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/genética , Proteômica , Sinapses/efeitos dos fármacos , Vias Neurais/efeitos dos fármacosRESUMO
PURPOSE: Limited research examines birth defects from maternal or paternal firefighting exposure. This study aims to assess if maternal or paternal occupational exposure to firefighting during periconception is associated with offspring birth defects. METHODS: Data from California birth certificates (2007-2019) were linked to maternal / offspring hospitalization records. Occupation during the periconceptional period was categorized from vital statistics as the following: paternal non-firefighting (n = 4,135,849), paternal firefighting (n = 22,732), maternal non-firefighting (n = 3,332,255) and maternal firefighting (n = 502). Birth defects were identified using ICD codes, grouped by anatomical regions. Adjusted odds ratios were estimated, and sensitivity analyses explored police officer reference groups and detailed birth defect categories. RESULTS: Offspring of paternal firefighters had lower odds of circulatory defects (aOR = 0.9, 95% CI 0.8, 1.0), oral clefts (aOR = 0.6, 95% CI 0.4, 0.8) and respiratory defects (0.7, 95% CI 0.6, 0.9) compared to paternal non-firefighters. Associations between maternal firefighting and offspring birth defects were imprecise. Substituting police officers as the reference group attenuated findings. CONCLUSIONS: Offspring of paternal firefighters may have similar or slightly lower birth defect odds compared to offspring of non-firefighters. Limited data was available for assessing maternal firefighting outcomes. Future studies should prioritize studies using occupational exposure matrices to limit misclassification of exposure.
RESUMO
Increasing use of unbiased genomic sequencing in critically ill infants can expand understanding of rare diseases such as Kabuki syndrome (KS). Infants diagnosed with KS through genome-wide sequencing performed during the initial hospitalization underwent retrospective review of medical records. Human phenotype ontology terms used in genomic analysis were aggregated and analyzed. Clinicians were surveyed regarding changes in management and other care changes. Fifteen infants met inclusion criteria. KS was not suspected prior to genomic sequencing. Variants were classified as Pathogenic (n = 10) or Likely Pathogenic (n = 5) by American College of Medical Genetics and Genomics Guidelines. Fourteen variants were de novo (KMT2D, n = 12, KDM6A, n = 2). One infant inherited a likely pathogenic variant in KMT2D from an affected father. Frequent findings involved cardiovascular (14/15) and renal (7/15) systems, with palatal defects also identified (6/15). Three infants had non-immune hydrops. No minor anomalies were universally documented; ear anomalies, micrognathia, redundant nuchal skin, and hypoplastic nails were common. Changes in management were reported in 14 infants. Early use of unbiased genome-wide sequencing enabled a molecular diagnosis prior to clinical recognition including infants with atypical or rarely reported features of KS while also expanding the phenotypic spectrum of this rare disorder.
Assuntos
Anormalidades Múltiplas , Doenças Hematológicas , Doenças Vestibulares , Gravidez , Feminino , Humanos , Lactente , Anormalidades Múltiplas/genética , Face/anormalidades , Doenças Hematológicas/genética , Doenças Vestibulares/genética , Fenótipo , Histona Desmetilases/genéticaRESUMO
BACKGROUND: Fetal alcohol spectrum disorders (FASD) are developmental disabilities that are estimated to occur in 2-5% of elementary school children and that negatively impact a child's ability to function without support. Timely diagnosis-informed interventions are crucial to optimizing the developmental trajectory of children with FASD. The true prevalence of FASD among children receiving services for developmental disabilities is unknown. METHODS: An FASD prevalence study was carried out between 2011 and 2014 among a sample of 5- to 7-year-old children who were receiving services provided by the California State Regional Center for Developmental Disabilities in San Diego County. Children whose parent or caregiver consented were evaluated using the Collaboration on Fetal Alcohol Spectrum Disorders Prevalence study assessment protocol and classification criteria. RESULTS: Among 216 eligible caregiver-child dyads, 44 completed assessments that were sufficient to obtain a classification for FASD, including fetal alcohol syndrome (FAS), partial FAS, alcohol-related neurodevelopmental disorder, or no fetal alcohol spectrum disorder. Fifteen children were classified as meeting the criteria for an FASD. A minimum FASD prevalence rate of 69.4 per 1000 (6.9%) among all eligible children was estimated. None of the children classified as FASD were receiving services because of an FASD diagnosis, and none had previously been diagnosed with FASD. Autism was the most common qualifying diagnosis for which children classified as FASD were receiving services. CONCLUSIONS: The 6.9% prevalence estimate among Regional Center clients was higher than the prevalence estimate of 2.3% in the same community among 5- to 7-year-old children in the general population, though the estimate was based on only 20% of eligible dyads. All children in the sample were receiving Regional Center services for another diagnosis. Barriers to eligibility for services for children with FASD may lead to less than optimum care for these children. Study findings support the facilitation of access to developmental services for children with FASD.
Assuntos
Transtornos do Espectro Alcoólico Fetal , Gravidez , Feminino , Humanos , Criança , Pré-Escolar , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Transtornos do Espectro Alcoólico Fetal/terapia , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos Transversais , Troca Materno-Fetal , PrevalênciaRESUMO
BACKGROUND: The fetal alcohol spectrum disorders (FASD) are among the most prevalent causes of neurodevelopmental disorders. The diagnosis is based on assessment of prenatal alcohol exposure, specific physical features identified with a dysmorphology examination, and neurobehavioral assessment. Prompt diagnosis of affected children is necessary to provide early intervention services in a timely manner; however, the availability of diagnostic expertise is limited. We propose telemedicine (TM) as a valid and reliable mode by which the physical phenotype of FASD can be accurately assessed. METHODS: We compared face-to-face (F2F) physical examinations of the 3 key facial features and the resulting physical phenotype of the fetal alcohol syndrome (FAS) and partial FAS (pFAS), as well as 12 additional physical features seen more frequently in children with FAS than in the general population in 61 individuals with 2 different TM methods. These included a Transportable Examination Station system using a precision camera and a laptop and a Zoom secure connection system (ZOOM), using a smart phone and a tablet. We measured the percentages of agreement and the Cohen's K coefficient for each comparison. RESULTS: Agreements for most physical features and for the physical phenotype of FAS and pFAS were in the "almost perfect" range with some exceptions in the "substantial" range. Imprecision in measurement and subjectivity underlie lower agreement for some features, both F2F and using TM. We identified the optimal conditions for the F2F examinations in order to assure reliability using TM. CONCLUSIONS: TM is a valid and reliable method for the examination of the physical features of FAS that may contribute to greater access to an early diagnosis of FASD in children prenatally exposed to alcohol and/or with characteristic neurobehavioral deficits.
Assuntos
Transtornos do Espectro Alcoólico Fetal/diagnóstico , Transtornos do Neurodesenvolvimento/diagnóstico , Exame Físico/métodos , Telemedicina/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Humanos , Lactente , Masculino , Transtornos do Neurodesenvolvimento/fisiopatologia , Exame Físico/instrumentação , Exame Físico/normas , Gravidez , Telemedicina/instrumentação , Telemedicina/normasRESUMO
MECP2 duplication syndrome (MDS) is an X-linked neurodevelopmental disorder characterized by a severe to profound intellectual disability, early onset hypotonia and diverse psycho-motor and behavioural features. To date, fewer than 200 cases have been published. We report the clinical and molecular characterization of a Spanish MDS cohort that included 19 boys and 2 girls. Clinical suspicions were confirmed by array comparative genomic hybridization and multiplex ligation-dependent probe amplification (MLPA). Using, a custom in-house MLPA assay, we performed a thorough study of the minimal duplicated region, from which we concluded a complete duplication of both MECP2 and IRAK1 was necessary for a correct MDS diagnosis, as patients with partial MECP2 duplications lacked some typical clinical traits present in other MDS patients. In addition, the duplication location may be related to phenotypic severity. This observation may provide a new approach for genotype-phenotype correlations, and thus more personalized genetic counselling.
Assuntos
Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Quinases Associadas a Receptores de Interleucina-1/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Proteína 2 de Ligação a Metil-CpG/genética , Adolescente , Adulto , Criança , Pré-Escolar , Cromossomos Humanos X/genética , Hibridização Genômica Comparativa , Deficiências do Desenvolvimento/patologia , Feminino , Estudos de Associação Genética , Humanos , Lactente , Deficiência Intelectual/patologia , Masculino , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Hipotonia Muscular/genética , Hipotonia Muscular/patologia , Linhagem , Medicina de Precisão , Adulto JovemRESUMO
BACKGROUND: Fetal alcohol syndrome (FAS) is a disorder caused by alterations in embryo-fetal development due to prenatal alcohol exposure. It is estimated that between 0.5 and 2 per 1,000 individuals are born with FAS every year. In Brazil, there are few studies addressing the extent of the problem of FAS/fetal alcohol spectrum disorders (FASD); these studies are confined to limited geographic areas. Therefore, we decided to perform a health needs assessment for FAS/FASD in Brazil. METHODS: To estimate the prevalence of FAS and FASD in Brazil, we used information from the literature, which estimates between 0.5 and 2/1,000 births per year for FAS and 10 to 50/1,000 for FASD. RESULTS: We estimated that approximately 1,500 to 6,000 children are born with FAS every year. Considering the whole population, the prevalence would be 95,377 to 380,000 affected people. However, when we consider FASD as a whole, we estimate that between 1,900,000 and 9,500,000 Brazilians might suffer the more severe consequences of alcohol exposure during pregnancy and be living with FASD. CONCLUSION: The results of the current study indicate that FAS and FASD are prevalent disorders in Brazil, and more policies targeting alcohol intake during pregnancy must be developed.
Assuntos
Transtornos do Espectro Alcoólico Fetal/epidemiologia , Avaliação das Necessidades , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Bebidas Alcoólicas/legislação & jurisprudência , Brasil/epidemiologia , Atenção à Saúde , Feminino , Humanos , Gravidez , Fatores SocioeconômicosRESUMO
(1) Background: Neosaxitoxin (NeoSTX) has been used as a local anesthetic, but its anti-inflammatory effects have not been well defined. In the present study, we investigate the effects of NeoSTX on lipopolysaccharide (LPS)-activated macrophages. (2) Methods: Raw 264.7 and equine PBMC cells were incubated with or without 100 ng/mL LPS in the presence or absence of NeoSTX (1µM). The expression of inflammatory mediators was assessed: nitric oxide (NO) content using the Griess assay, TNF-α content using the ELISA assay, and mRNA of inducible nitric oxide synthase (iNOS), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) using a real-time polymerase chain reaction. (3) Results: NeoSTX (1 µM) significantly inhibited the release of NO, TNF-α, and expression of iNOS, IL-1ß, and TNF-α in LPS-activated macrophages of both species studied. Furthermore, our study shows that the LPS-induced release of inflammatory mediators was suppressed by NeoSTX. Additionally, NeoSTX deactivated polarized macrophages to M1 by LPS without compromising its polarization towards M2. (4) Conclusions: NeoSTX inhibits LPS-induced release of inflammatory mediators from macrophages, and these effects may be mediated by the blockade of voltage-gated sodium channels (VGSC).
Assuntos
Mediadores da Inflamação/farmacologia , Inflamação/prevenção & controle , Macrófagos/efeitos dos fármacos , Saxitoxina/análogos & derivados , Animais , Humanos , Lipopolissacarídeos , Camundongos , Células RAW 264.7/efeitos dos fármacos , Saxitoxina/farmacologiaRESUMO
BackgroundFetal alcohol syndrome (FAS) is caused by maternal alcohol consumption during pregnancy; although additional factors might be involved, as development and severity are not directly related to alcohol intake. The abnormal glycosylation caused by alcohol might play a role in FAS according to the clinical similarities shared with congenital disorders of glycosylation (CDG). Thus, mutations underlying CDG, affecting genes involved in glycosylation, could also be involved in FAS.MethodsA panel of 74 genes involved in N-glycosylation was sequenced in 25 FAS patients and 20 controls with prenatal alcohol exposure. Transferrin glycoforms were evaluated by HPLC.ResultsRare (minor allele frequency<0.009) missense/splice site variants were more frequent in FAS than controls (84% vs. 50%; P=0.034, odds ratio: 5.25, 95% confidence interval: 1.3-20.9). Remarkably, three patients, but no controls, carried variants with functional effects identified in CDG patients. Moreover, the patient with the most severe clinical phenotype was the only one carrying two variants with functional effects. Family studies support that the combination of a genetic defect and alcohol consumption during pregnancy might have a role in FAS development.ConclusionsOur study supports that the rare variants of genes involved in N-glycosylation could play a role in the development and severity of FAS under prenatal alcohol exposure.
Assuntos
Defeitos Congênitos da Glicosilação/genética , Transtornos do Espectro Alcoólico Fetal/genética , Predisposição Genética para Doença , Mutação , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Defeitos Congênitos da Glicosilação/complicações , Feminino , Variação Genética , Glicosilação , Humanos , Lactente , Masculino , Exposição Materna , Pessoa de Meia-Idade , Mães , Razão de Chances , Gravidez , Estudos Retrospectivos , Análise de Sequência de DNA , Transferrina/químicaRESUMO
Hemocyanins induce a potent Th1-dominant immune response with beneficial clinical outcomes when used as a carrier/adjuvant in vaccines and nonspecific immunostimulant in cancer. However, the mechanisms by which hemocyanins trigger innate immune responses, leading to beneficial adaptive immune responses, are unknown. This response is triggered by a proinflammatory signal from various components, of which macrophages are an essential part. To understand how these proteins influence macrophage response, we investigated the effects of mollusks hemocyanins with varying structural and immunological properties, including hemocyanins from Concholepas concholepas, Fissurella latimarginata, and Megathura crenulata (keyhole limpet hemocyanin), on cultures of peritoneal macrophages. Hemocyanins were phagocytosed and slowly processed. Analysis of this process showed differential gene expression along with protein levels of proinflammatory markers, including IL-1ß, IL-6, IL-12p40, and TNF-α. An extended expression analysis of 84 cytokines during a 24-h period showed a robust proinflammatory response for F. latimarginata hemocyanin in comparison with keyhole limpet hemocyanin and C. concholepas hemocyanin, which was characterized by an increase in the transcript levels of M1 cytokines involved in leukocyte recruitment. These cytokine genes included chemokines (Cxcl1, Cxcl3, Cxcl5, Ccl2, and Ccl3), ILs (Il1b and Ifng), growth factors (Csf2 and Csf3), and TNF family members (Cd40lg). The protein levels of certain cytokines were increased. However, every hemocyanin maintains downregulated key M2 cytokine genes, including Il4 and Il5 Collectively, our data demonstrate that hemocyanins are able to trigger the release of proinflammatory factors with different patterns of cytokine expression, suggesting differential signaling pathways and transcriptional network mechanisms that lead to the activation of M1-polarized macrophages.
Assuntos
Citocinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Hemocianinas/farmacologia , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Animais , Citocinas/imunologia , Regulação para Baixo/efeitos dos fármacos , Imunidade Inata/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo , TranscriptomaRESUMO
Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, structural differences among the hemocyanins of various mollusks may affect their physicochemical properties. Here, we studied the oxygen-binding cooperativity and affinity of Concholepas concholepas hemocyanin (CCH) and its two isolated subunits over a wide range of temperatures and pH values. Considering the differences in the quaternary structures of CCH and keyhole limpet hemocyanin (KLH), we hypothesized that the heterodidecameric CCH has different oxygen-binding parameters than the homodidecameric KLH. A novel modification of the polarographic method was applied in which rat liver submitochondrial particles containing cytochrome c oxidase were introduced to totally deplete oxygen of the test solution using ascorbate as the electron donor. This method was both sensitive and reproducible. The results showed that CCH, like other hemocyanins, exhibits cooperativity, showing an inverse relationship between the oxygen-binding parameters and temperature. According to their Hill coefficients, KLH has greater cooperativity than CCH at physiological pH; however, CCH is less sensitive to pH changes than KLH. Appreciable differences in binding behavior were found between the CCH subunits: the cooperativity of CCH-A was not only almost double that of CCH-B, but it was also slightly superior to that of CCH, thus suggesting that the oxygen-binding domains of the CCH subunits are different in their primary structure. Collectively, these data suggest that CCH-A is the main oxygen-binding domain in CCH; CCH-B may play a more structural role, perhaps utilizing its surprising predisposition to form tubular polymers, unlike CCH-A, as demonstrated here using electron microscopy.
Assuntos
Hemocianinas/metabolismo , Moluscos/química , Oxigênio/metabolismo , Animais , Hemocianinas/química , Concentração de Íons de Hidrogênio , Domínios Proteicos , Subunidades ProteicasRESUMO
In October 2015, Zika virus (ZIKV) outbreak the Brazilian Ministry of Health (MoH). In response, the Brazilian Society of Medical Genetics established a task force (SBGM-ZETF) to study the phenotype of infants born with microcephaly due to ZIKV congenital infection and delineate the phenotypic spectrum of this newly recognized teratogen. This study was based on the clinical evaluation and neuroimaging of 83 infants born during the period from July, 2015 to March, 2016 and registered by the SBGM-ZETF. All 83 infants had significant findings on neuroimaging consistent with ZIKV congenital infection and 12 had confirmed ZIKV IgM in CSF. A recognizable phenotype of microcephaly, anomalies of the shape of skull and redundancy of the scalp consistent with the Fetal Brain Disruption Sequence (FBDS) was present in 70% of infants, but was most often subtle. In addition, features consistent with fetal immobility, ranging from dimples (30.1%), distal hand/finger contractures (20.5%), and feet malpositions (15.7%), to generalized arthrogryposis (9.6%), were present in these infants. Some cases had milder microcephaly or even a normal head circumference (HC), and other less distinctive findings. The detailed observation of the dysmorphic and neurologic features in these infants provides insight into the mechanisms and timings of the brain disruption and the sequence of developmental anomalies that may occur after prenatal infection by the ZIKV.
Assuntos
Surtos de Doenças , Doenças Fetais/epidemiologia , Microcefalia/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Infecção por Zika virus/epidemiologia , Anticorpos Antivirais/líquido cefalorraquidiano , Encéfalo/anormalidades , Encéfalo/virologia , Brasil/epidemiologia , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/patologia , Feto , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Lactente , Microcefalia/complicações , Microcefalia/diagnóstico por imagem , Microcefalia/patologia , Neuroimagem , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/patologia , Síndrome , Zika virus/crescimento & desenvolvimento , Zika virus/imunologia , Zika virus/patogenicidade , Infecção por Zika virus/complicações , Infecção por Zika virus/diagnóstico por imagem , Infecção por Zika virus/patologiaRESUMO
BACKGROUND: The rate of unscheduled return visits is often used as a quality-of-care indicator in EDs, although its validity is not yet fully established. Our aim was to identify the characteristics of return visits that may be attributed to problems in quality of care. METHODS: Retrospective paired review of medical charts in a random sample of return visits during the 72â hours following discharge from the ED in three hospitals of Andalusia, Spain in 2013. Charts were reviewed by senior medical physicians to determine which return visits reflected quality-of-care problems. Time frame for return visit, index and return visit acuity, disposition and diagnosis were compared with determine which variables were associated with a quality problem. Sensitivity and specificity for each variable to indicate a quality problem were determined. RESULTS: We studied the causes of 895 return visits, finding that 65 (7.3%) were due to inadequate quality of care in the index visit. Potentially avoidable return visits were more common in more severely ill patients, in those with greater severity in the return than in the index visit and in patients hospitalised after the return. The combination of this three variables presented sensitivity 66% and specificity 68% in identification of quality-related returns. CONCLUSIONS: The overall level of return visits cannot be considered a valid indicator of quality of care. However, certain specific variables, including the level of severity of the patient's condition or the discharge destination following the return visits, could be considered valid in this respect.
Assuntos
Serviço Hospitalar de Emergência/normas , Readmissão do Paciente/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Resultado do Tratamento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/normas , Qualidade da Assistência à Saúde/estatística & dados numéricos , Estudos Retrospectivos , EspanhaRESUMO
Cornelia de Lange syndrome (CdLS) is a multisystem genetic disorder with distinct facies, growth failure, intellectual disability, distal limb anomalies, gastrointestinal and neurological disease. Mutations in NIPBL, encoding a cohesin regulatory protein, account for >80% of cases with typical facies. Mutations in the core cohesin complex proteins, encoded by the SMC1A, SMC3 and RAD21 genes, together account for â¼5% of subjects, often with atypical CdLS features. Recently, we identified mutations in the X-linked gene HDAC8 as the cause of a small number of CdLS cases. Here, we report a cohort of 38 individuals with an emerging spectrum of features caused by HDAC8 mutations. For several individuals, the diagnosis of CdLS was not considered prior to genomic testing. Most mutations identified are missense and de novo. Many cases are heterozygous females, each with marked skewing of X-inactivation in peripheral blood DNA. We also identified eight hemizygous males who are more severely affected. The craniofacial appearance caused by HDAC8 mutations overlaps that of typical CdLS but often displays delayed anterior fontanelle closure, ocular hypertelorism, hooding of the eyelids, a broader nose and dental anomalies, which may be useful discriminating features. HDAC8 encodes the lysine deacetylase for the cohesin subunit SMC3 and analysis of the functional consequences of the missense mutations indicates that all cause a loss of enzymatic function. These data demonstrate that loss-of-function mutations in HDAC8 cause a range of overlapping human developmental phenotypes, including a phenotypically distinct subgroup of CdLS.
Assuntos
Fontanelas Cranianas/anormalidades , Síndrome de Cornélia de Lange/enzimologia , Anormalidades do Olho/enzimologia , Genes Ligados ao Cromossomo X , Histona Desacetilases/genética , Hipertelorismo/enzimologia , Proteínas Repressoras/genética , Sequência de Aminoácidos , Criança , Pré-Escolar , Estudos de Coortes , Fontanelas Cranianas/enzimologia , Síndrome de Cornélia de Lange/genética , Anormalidades do Olho/genética , Feminino , Histona Desacetilases/química , Histona Desacetilases/metabolismo , Humanos , Hipertelorismo/genética , Lactente , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Fenótipo , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Alinhamento de SequênciaRESUMO
BACKGROUND: Williams-Beuren syndrome (WBS, OMIM-194050) is a neurodevelopmental disorder with multisystemic manifestations caused by a 1.55-1.83 Mb deletion at 7q11.23 including 26-28 genes. Reported endocrine and metabolic abnormalities include transient hypercalcaemia of infancy, subclinical hypothyroidism in â¼ 30% of children and impaired glucose tolerance in â¼ 75% of adult individuals. The purpose of this study was to further study metabolic alterations in patients with WBS, as well as in several mouse models, to establish potential candidate genes. METHODS: We analysed several metabolic parameters in a cohort of 154 individuals with WBS (data available from 69 to 151 cases per parameter), as well as in several mouse models with complete and partial deletions of the orthologous WBS locus, and searched for causative genes and potential modifiers. RESULTS: Triglyceride plasma levels were significantly decreased in individuals with WBS while cholesterol levels were slightly decreased compared with controls. Hyperbilirubinemia, mostly unconjugated, was found in 18.3% of WBS cases and correlated with subclinical hypothyroidism and hypotriglyceridemia, suggesting common pathogenic mechanisms. Haploinsufficiency at MLXIPL and increased penetrance for hypomorphic alleles at the UGT1A1 gene promoter might underlie the lipid and bilirubin alterations. Other disturbances included increased protein and iron levels, as well as the known subclinical hypothyroidism and glucose intolerance. CONCLUSIONS: Our results show that several unreported biochemical alterations, related to haploinsufficiency for specific genes at 7q11.23, are relatively common in WBS. The early diagnosis, follow-up and management of these metabolic disturbances could prevent long-term complications in this disorder.
Assuntos
Hipotireoidismo/metabolismo , Doenças Metabólicas/metabolismo , Síndrome de Williams/metabolismo , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Modelos Animais de Doenças , Feminino , Humanos , Hipotireoidismo/fisiopatologia , Masculino , Doenças Metabólicas/fisiopatologia , Camundongos , Síndrome de Williams/genética , Síndrome de Williams/fisiopatologia , Adulto JovemRESUMO
Bi-allelic variants in CHST14, encoding dermatan 4-O-sulfotransferase-1 (D4ST1), cause musculocontractural Ehlers-Danlos syndrome (MC-EDS), a recessive disorder characterized by connective tissue fragility, craniofacial abnormalities, congenital contractures, and developmental anomalies. Recently, the identification of bi-allelic variants in DSE, encoding dermatan sulfate epimerase-1 (DS-epi1), in a child with MC-EDS features, suggested locus heterogeneity for this condition. DS-epi1 and D4ST1 are crucial for biosynthesis of dermatan sulfate (DS) moieties in the hybrid chondroitin sulfate (CS)/DS glycosaminoglycans (GAGs). Here, we report four novel families with severe MC-EDS caused by unique homozygous CHST14 variants and the second family with a homozygous DSE missense variant, presenting a somewhat milder MC-EDS phenotype. The glycanation of the dermal DS proteoglycan decorin is impaired in fibroblasts from D4ST1- as well as DS-epi1-deficient patients. However, in D4ST1-deficiency, the decorin GAG is completely replaced by CS, whereas in DS-epi1-deficiency, still some DS moieties are present. The multisystemic abnormalities observed in our patients support a tight spatiotemporal control of the balance between CS and DS, which is crucial for multiple processes including cell differentiation, organ development, cell migration, coagulation, and connective tissue integrity.
Assuntos
Dermatan Sulfato/biossíntese , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/metabolismo , Heterogeneidade Genética , Fenótipo , Adolescente , Adulto , Sequência de Aminoácidos , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Biópsia , Criança , Colágeno/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Síndrome de Ehlers-Danlos/diagnóstico , Éxons , Matriz Extracelular/metabolismo , Fácies , Feminino , Fibronectinas/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Linhagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Pele/patologia , Pele/ultraestrutura , Sulfotransferases/química , Sulfotransferases/genética , Sulfotransferases/metabolismo , Adulto JovemRESUMO
Already 40 genes have been identified for autosomal-recessive nonsyndromic hearing impairment (arNSHI); however, many more genes are still to be identified. In a Dutch family segregating arNSHI, homozygosity mapping revealed a 2.4 Mb homozygous region on chromosome 11 in p15.1-15.2, which partially overlapped with the previously described DFNB18 locus. However, no putative pathogenic variants were found in USH1C, the gene mutated in DFNB18 hearing impairment. The homozygous region contained 12 additional annotated genes including OTOG, the gene encoding otogelin, a component of the tectorial membrane. It is thought that otogelin contributes to the stability and strength of this membrane through interaction or stabilization of its constituent fibers. The murine orthologous gene was already known to cause hearing loss when defective. Analysis of OTOG in the Dutch family revealed a homozygous 1 bp deletion, c.5508delC, which leads to a shift in the reading frame and a premature stop codon, p.Ala1838ProfsX31. Further screening of 60 unrelated probands from Spanish arNSHI families detected compound heterozygous OTOG mutations in one family, c.6347C>T (p.Pro2116Leu) and c. 6559C>T (p.Arg2187X). The missense mutation p.Pro2116Leu affects a highly conserved residue in the fourth von Willebrand factor type D domain of otogelin. The subjects with OTOG mutations have a moderate hearing impairment, which can be associated with vestibular dysfunction. The flat to shallow "U" or slightly downsloping shaped audiograms closely resembled audiograms of individuals with recessive mutations in the gene encoding α-tectorin, another component of the tectorial membrane. This distinctive phenotype may represent a clue to orientate the molecular diagnosis.
Assuntos
Genes Recessivos , Perda Auditiva Neurossensorial/genética , Glicoproteínas de Membrana/genética , Mutação , Homozigoto , Humanos , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , IrmãosRESUMO
Copy number variants (CNVs) of the Williams-Beuren syndrome (WBS) 7q11.23 region are responsible for neurodevelopmental disorders with multisystem involvement and variable expressivity. We found 2 patients with a deletion and 1 patient with a duplication in this region sharing a common breakpoint located between the LIMK1 and EIF4H(WBSCR1) genes. One patient had a WBS phenotype, although testing with a commercially available FISH assay was negative for the deletion. A further test using array CGH showed an atypical WBS region deletion. The second patient showed global developmental delay, speech delay and poor motor skills with a deletion outside the WBS region. The third patient had manifestations compatible with an autism spectrum disorder showing a duplication in the WBS region. Our findings point to the existence of a previously unrecognized recurrent breakpoint responsible for rearrangements in the WBS region. Given that most commercial FISH assays include probes flanking this novel breakpoint, further testing with array CGH should be performed in patients with WBS and negative FISH results.
Assuntos
Sítios Frágeis do Cromossomo , Síndrome de Williams/genética , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Humanos , MasculinoRESUMO
Despite remarkable progress in identifying causal genes for many types of genetic lipodystrophies in the last decade, the molecular basis of many extremely rare lipodystrophy patients with distinctive phenotypes remains unclear. We conducted whole exome sequencing of the parents and probands from six pedigrees with neonatal onset of generalized loss of subcutaneous fat with additional distinctive phenotypic features and report de novo heterozygous null mutations, c.424C>T (p.Q142*) and c.479_480delTT (p.F160*), in CAV1 in a 7-year-old male and a 3-year-old female of European origin, respectively. Both the patients had generalized fat loss, thin mottled skin and progeroid features at birth. The male patient had cataracts requiring extraction at age 30 months and the female patient had pulmonary arterial hypertension. Dermal fibroblasts of the female patient revealed negligible CAV1 immunofluorescence staining compared to control but there were no differences in the number and morphology of caveolae upon electron microscopy examination. Based upon the similarities in the clinical features of these two patients, previous reports of CAV1 mutations in patients with lipodystrophies and pulmonary hypertension, and similar features seen in CAV1 null mice, we conclude that these variants are the most likely cause of one subtype of neonatal onset generalized lipodystrophy syndrome.