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1.
Proc Natl Acad Sci U S A ; 120(21): e2302584120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186866

RESUMO

Mutations in the TMEM260 gene cause structural heart defects and renal anomalies syndrome, but the function of the encoded protein remains unknown. We previously reported wide occurrence of O-mannose glycans on extracellular immunoglobulin, plexin, transcription factor (IPT) domains found in the hepatocyte growth factor receptor (cMET), macrophage-stimulating protein receptor (RON), and plexin receptors, and further demonstrated that two known protein O-mannosylation systems orchestrated by the POMT1/2 and transmembrane and tetratricopeptide repeat-containing proteins 1-4 gene families were not required for glycosylation of these IPT domains. Here, we report that the TMEM260 gene encodes an ER-located protein O-mannosyltransferase that selectively glycosylates IPT domains. We demonstrate that disease-causing TMEM260 mutations impair O-mannosylation of IPT domains and that TMEM260 knockout in cells results in receptor maturation defects and abnormal growth of 3D cell models. Thus, our study identifies the third protein-specific O-mannosylation pathway in mammals and demonstrates that O-mannosylation of IPT domains serves critical functions during epithelial morphogenesis. Our findings add a new glycosylation pathway and gene to a growing group of congenital disorders of glycosylation.


Assuntos
Manose , Manosiltransferases , Animais , Glicosilação , Mamíferos/metabolismo , Manose/metabolismo , Manosiltransferases/genética , Manosiltransferases/metabolismo
2.
Am J Hum Genet ; 109(10): 1932-1943, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36206744

RESUMO

Proteins containing the FERM (four-point-one, ezrin, radixin, and moesin) domain link the plasma membrane with cytoskeletal structures at specific cellular locations and have been implicated in the localization of cell-membrane-associated proteins and/or phosphoinositides. FERM domain-containing protein 5 (FRMD5) localizes at cell adherens junctions and stabilizes cell-cell contacts. To date, variants in FRMD5 have not been associated with a Mendelian disease in OMIM. Here, we describe eight probands with rare heterozygous missense variants in FRMD5 who present with developmental delay, intellectual disability, ataxia, seizures, and abnormalities of eye movement. The variants are de novo in all for whom parental testing was available (six out of eight probands), and human genetic datasets suggest that FRMD5 is intolerant to loss of function (LoF). We found that the fly ortholog of FRMD5, CG5022 (dFrmd), is expressed in the larval and adult central nervous systems where it is present in neurons but not in glia. dFrmd LoF mutant flies are viable but are extremely sensitive to heat shock, which induces severe seizures. The mutants also exhibit defective responses to light. The human FRMD5 reference (Ref) cDNA rescues the fly dFrmd LoF phenotypes. In contrast, all the FRMD5 variants tested in this study (c.340T>C, c.1051A>G, c.1053C>G, c.1054T>C, c.1045A>C, and c.1637A>G) behave as partial LoF variants. In addition, our results indicate that two variants that were tested have dominant-negative effects. In summary, the evidence supports that the observed variants in FRMD5 cause neurological symptoms in humans.


Assuntos
Deficiência Intelectual , Animais , Ataxia/genética , DNA Complementar , Deficiências do Desenvolvimento/genética , Movimentos Oculares , Humanos , Deficiência Intelectual/genética , Proteínas de Membrana , Fosfatidilinositóis , Convulsões , Proteínas Supressoras de Tumor/genética
3.
Genet Med ; 25(8): 100863, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37125634

RESUMO

PURPOSE: Bone morphogenic proteins (BMPs) regulate gene expression that is related to many critical developmental processes, including osteogenesis for which they are named. In addition, BMP2 is widely expressed in cells of mesenchymal origin, including bone, cartilage, skeletal and cardiac muscle, and adipose tissue. It also participates in neurodevelopment by inducing differentiation of neural stem cells. In humans, BMP2 variants result in a multiple congenital anomaly syndrome through a haploinsufficiency mechanism. We sought to expand the phenotypic spectrum and highlight phenotypes of patients harboring monoallelic missense variants in BMP2. METHODS: We used retrospective chart review to examine phenotypes from an international cohort of 18 individuals and compared these with published cases. Patient-derived missense variants were modeled in zebrafish to examine their effect on the ability of bmp2b to promote embryonic ventralization. RESULTS: The presented cases recapitulated existing descriptions of BMP2-related disorders, including craniofacial, cardiac, and skeletal anomalies and exhibit a wide phenotypic spectrum. We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies. Missense variants modeled in zebrafish resulted in loss of protein function. CONCLUSION: We use this expansion of reported phenotypes to suggest multidisciplinary medical monitoring and management of patients with BMP2-related skeletal dysplasia spectrum.


Assuntos
Osteocondrodisplasias , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/genética , Estudos Retrospectivos , Diferenciação Celular , Osteogênese/genética , Proteínas Morfogenéticas Ósseas , Proteína Morfogenética Óssea 2/genética
4.
Clin Genet ; 101(2): 255-259, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713892

RESUMO

The developmental disorder Burn-McKeown Syndrome (BMKS) is characterised by choanal atresia and specific craniofacial features. BMKS is caused by biallelic variants in the pre-messenger RNA splicing factor TXNL4A. Most patients have a loss-of-function variant in trans with a 34-base pair (bp) deletion (type 1 Δ34) in the promoter region. Here, we identified two patients with BMKS. One individual has a TXNL4A c.93_94delCC, p.His32Argfs *21 variant combined with a type 1 Δ34 promoter deletion. The other has an intronic TXNL4A splice site variant (c.258-3C>G) and a type 1 Δ34 promoter deletion. We show the c.258-3C>G variant and a previously reported c.258-2A>G variant, cause skipping of the final exon of TXNL4A in a minigene splicing assay. Furthermore, we identify putative transcription factor binding sites within the 56 bp of the TXNL4A promoter affected by the type 1 and type 2 Δ34 and use dual luciferase assays to identify a 22 bp repeated motif essential for TXNL4A expression within this promoter region. We propose that additional variants affecting critical transcription factor binding nucleotides within the 22 bp repeated motif could be relevant to BMKS aetiology. Finally, our data emphasises the need to analyse the non-coding sequence in individuals where a single likely pathogenic coding variant is identified in an autosomal recessive disorder consistent with the clinical presentation.


Assuntos
Atresia das Cóanas/diagnóstico , Atresia das Cóanas/genética , Surdez/congênito , Genótipo , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Mutação , Ribonucleoproteína Nuclear Pequena U5/genética , Alelos , Sítios de Ligação , Surdez/diagnóstico , Surdez/genética , Fácies , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Linhagem , Fenótipo , Regiões Promotoras Genéticas , Ligação Proteica , Splicing de RNA , Ribonucleoproteína Nuclear Pequena U5/metabolismo , Fatores de Transcrição/metabolismo
5.
Am J Med Genet A ; 188(12): 3492-3504, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36135330

RESUMO

Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a life-threatening birth defect that often occurs with other major birth defects (EA/TEF+). Despite advances in genetic testing, a molecular diagnosis can only be made in a minority of EA/TEF+ cases. Here, we analyzed clinical exome sequencing data and data from the DECIPHER database to determine the efficacy of exome sequencing in cases of EA/TEF+ and to identify phenotypic expansions involving EA/TEF. Among 67 individuals with EA/TEF+ referred for clinical exome sequencing, a definitive or probable diagnosis was made in 11 cases for an efficacy rate of 16% (11/67). This efficacy rate is significantly lower than that reported for other major birth defects, suggesting that polygenic, multifactorial, epigenetic, and/or environmental factors may play a particularly important role in EA/TEF pathogenesis. Our cohort included individuals with pathogenic or likely pathogenic variants that affect TCF4 and its downstream target NRXN1, and FANCA, FANCB, and FANCC, which are associated with Fanconi anemia. These cases, previously published case reports, and comparisons to other EA/TEF genes made using a machine learning algorithm, provide evidence in support of a potential pathogenic role for these genes in the development of EA/TEF.


Assuntos
Atresia Esofágica , Fístula Traqueoesofágica , Humanos , Fístula Traqueoesofágica/diagnóstico , Fístula Traqueoesofágica/genética , Fístula Traqueoesofágica/complicações , Atresia Esofágica/diagnóstico , Atresia Esofágica/genética , Atresia Esofágica/complicações , Exoma/genética , Sequenciamento do Exoma
6.
Genet Med ; 23(2): 352-362, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33106617

RESUMO

PURPOSE: Neurodevelopmental disorders (NDD) caused by protein phosphatase 2A (PP2A) dysfunction have mainly been associated with de novo variants in PPP2R5D and PPP2CA, and more rarely in PPP2R1A. Here, we aimed to better understand the latter by characterizing 30 individuals with de novo and often recurrent variants in this PP2A scaffolding Aα subunit. METHODS: Most cases were identified through routine clinical diagnostics. Variants were biochemically characterized for phosphatase activity and interaction with other PP2A subunits. RESULTS: We describe 30 individuals with 16 different variants in PPP2R1A, 21 of whom had variants not previously reported. The severity of developmental delay ranged from mild learning problems to severe intellectual disability (ID) with or without epilepsy. Common features were language delay, hypotonia, and hypermobile joints. Macrocephaly was only seen in individuals without B55α subunit-binding deficit, and these patients had less severe ID and no seizures. Biochemically more disruptive variants with impaired B55α but increased striatin binding were associated with profound ID, epilepsy, corpus callosum hypoplasia, and sometimes microcephaly. CONCLUSION: We significantly expand the phenotypic spectrum of PPP2R1A-related NDD, revealing a broader clinical presentation of the patients and that the functional consequences of the variants are more diverse than previously reported.


Assuntos
Deficiência Intelectual , Microcefalia , Transtornos do Neurodesenvolvimento , Humanos , Deficiência Intelectual/genética , Hipotonia Muscular , Transtornos do Neurodesenvolvimento/epidemiologia , Transtornos do Neurodesenvolvimento/genética , Proteína Fosfatase 2/genética , Fatores de Transcrição
7.
Lancet ; 393(10173): 747-757, 2019 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-30712880

RESUMO

BACKGROUND: Fetal structural anomalies, which are detected by ultrasonography, have a range of genetic causes, including chromosomal aneuploidy, copy number variations (CNVs; which are detectable by chromosomal microarrays), and pathogenic sequence variants in developmental genes. Testing for aneuploidy and CNVs is routine during the investigation of fetal structural anomalies, but there is little information on the clinical usefulness of genome-wide next-generation sequencing in the prenatal setting. We therefore aimed to evaluate the proportion of fetuses with structural abnormalities that had identifiable variants in genes associated with developmental disorders when assessed with whole-exome sequencing (WES). METHODS: In this prospective cohort study, two groups in Birmingham and London recruited patients from 34 fetal medicine units in England and Scotland. We used whole-exome sequencing (WES) to evaluate the presence of genetic variants in developmental disorder genes (diagnostic genetic variants) in a cohort of fetuses with structural anomalies and samples from their parents, after exclusion of aneuploidy and large CNVs. Women were eligible for inclusion if they were undergoing invasive testing for identified nuchal translucency or structural anomalies in their fetus, as detected by ultrasound after 11 weeks of gestation. The partners of these women also had to consent to participate. Sequencing results were interpreted with a targeted virtual gene panel for developmental disorders that comprised 1628 genes. Genetic results related to fetal structural anomaly phenotypes were then validated and reported postnatally. The primary endpoint, which was assessed in all fetuses, was the detection of diagnostic genetic variants considered to have caused the fetal developmental anomaly. FINDINGS: The cohort was recruited between Oct 22, 2014, and June 29, 2017, and clinical data were collected until March 31, 2018. After exclusion of fetuses with aneuploidy and CNVs, 610 fetuses with structural anomalies and 1202 matched parental samples (analysed as 596 fetus-parental trios, including two sets of twins, and 14 fetus-parent dyads) were analysed by WES. After bioinformatic filtering and prioritisation according to allele frequency and effect on protein and inheritance pattern, 321 genetic variants (representing 255 potential diagnoses) were selected as potentially pathogenic genetic variants (diagnostic genetic variants), and these variants were reviewed by a multidisciplinary clinical review panel. A diagnostic genetic variant was identified in 52 (8·5%; 95% CI 6·4-11·0) of 610 fetuses assessed and an additional 24 (3·9%) fetuses had a variant of uncertain significance that had potential clinical usefulness. Detection of diagnostic genetic variants enabled us to distinguish between syndromic and non-syndromic fetal anomalies (eg, congenital heart disease only vs a syndrome with congenital heart disease and learning disability). Diagnostic genetic variants were present in 22 (15·4%) of 143 fetuses with multisystem anomalies (ie, more than one fetal structural anomaly), nine (11·1%) of 81 fetuses with cardiac anomalies, and ten (15·4%) of 65 fetuses with skeletal anomalies; these phenotypes were most commonly associated with diagnostic variants. However, diagnostic genetic variants were least common in fetuses with isolated increased nuchal translucency (≥4·0 mm) in the first trimester (in three [3·2%] of 93 fetuses). INTERPRETATION: WES facilitates genetic diagnosis of fetal structural anomalies, which enables more accurate predictions of fetal prognosis and risk of recurrence in future pregnancies. However, the overall detection of diagnostic genetic variants in a prospectively ascertained cohort with a broad range of fetal structural anomalies is lower than that suggested by previous smaller-scale studies of fewer phenotypes. WES improved the identification of genetic disorders in fetuses with structural abnormalities; however, before clinical implementation, careful consideration should be given to case selection to maximise clinical usefulness. FUNDING: UK Department of Health and Social Care and The Wellcome Trust.


Assuntos
Cariótipo Anormal/estatística & dados numéricos , Anormalidades Congênitas/genética , Sequenciamento do Exoma/estatística & dados numéricos , Desenvolvimento Fetal/genética , Feto/anormalidades , Cariótipo Anormal/embriologia , Aborto Eugênico/estatística & dados numéricos , Aborto Espontâneo/epidemiologia , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/epidemiologia , Variações do Número de Cópias de DNA/genética , Feminino , Feto/diagnóstico por imagem , Humanos , Recém-Nascido , Nascido Vivo/epidemiologia , Masculino , Medição da Translucência Nucal , Pais , Morte Perinatal/etiologia , Gravidez , Estudos Prospectivos , Natimorto/epidemiologia , Sequenciamento do Exoma/métodos
8.
Hum Mutat ; 40(6): 765-787, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30825406

RESUMO

Inherited retinal disorders (IRD) represent clinically and genetically heterogeneous diseases. To date, pathogenic variants have been identified in ~260 genes. Albeit that many genes are implicated in IRD, for 30-50% of the cases, the gene defect is unknown. These cases may be explained by novel gene defects, by overlooked structural variants, by variants in intronic, promoter or more distant regulatory regions, and represent synonymous variants of known genes contributing to the dysfunction of the respective proteins. Patients with one subgroup of IRD, namely incomplete congenital stationary night blindness (icCSNB), show a very specific phenotype. The major cause of this condition is the presence of a hemizygous pathogenic variant in CACNA1F. A comprehensive study applying direct Sanger sequencing of the gene-coding regions, exome and genome sequencing applied to a large cohort of patients with a clinical diagnosis of icCSNB revealed indeed that seven of the 189 CACNA1F-related cases have intronic and synonymous disease-causing variants leading to missplicing as validated by minigene approaches. These findings highlight that gene-locus sequencing may be a very efficient method in detecting disease-causing variants in clinically well-characterized patients with a diagnosis of IRD, like icCSNB.


Assuntos
Canais de Cálcio Tipo L/genética , Oftalmopatias Hereditárias/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Mutação , Miopia/genética , Cegueira Noturna/genética , Análise de Sequência de DNA/métodos , Predisposição Genética para Doença , Hemizigoto , Humanos , Íntrons , Masculino , Linhagem , Splicing de RNA , Mutação Silenciosa
10.
Am J Hum Genet ; 97(3): 475-82, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26299364

RESUMO

Adams-Oliver syndrome (AOS) is a rare developmental disorder characterized by the presence of aplasia cutis congenita (ACC) of the scalp vertex and terminal limb-reduction defects. Cardiovascular anomalies are also frequently observed. Mutations in five genes have been identified as a cause for AOS prior to this report. Mutations in EOGT and DOCK6 cause autosomal-recessive AOS, whereas mutations in ARHGAP31, RBPJ, and NOTCH1 lead to autosomal-dominant AOS. Because RBPJ, NOTCH1, and EOGT are involved in NOTCH signaling, we hypothesized that mutations in other genes involved in this pathway might also be implicated in AOS pathogenesis. Using a candidate-gene-based approach, we prioritized DLL4, a critical NOTCH ligand, due to its essential role in vascular development in the context of cardiovascular features in AOS-affected individuals. Targeted resequencing of the DLL4 gene with a custom enrichment panel in 89 independent families resulted in the identification of seven mutations. A defect in DLL4 was also detected in two families via whole-exome or genome sequencing. In total, nine heterozygous mutations in DLL4 were identified, including two nonsense and seven missense variants, the latter encompassing four mutations that replace or create cysteine residues, which are most likely critical for maintaining structural integrity of the protein. Affected individuals with DLL4 mutations present with variable clinical expression with no emerging genotype-phenotype correlations. Our findings demonstrate that DLL4 mutations are an additional cause of autosomal-dominant AOS or isolated ACC and provide further evidence for a key role of NOTCH signaling in the etiology of this disorder.


Assuntos
Displasia Ectodérmica/genética , Displasia Ectodérmica/patologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/patologia , Mutação/genética , Dermatoses do Couro Cabeludo/congênito , Transdução de Sinais/genética , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Ligação ao Cálcio , Heterozigoto , Humanos , Dados de Sequência Molecular , Linhagem , Receptores Notch/genética , Dermatoses do Couro Cabeludo/genética , Dermatoses do Couro Cabeludo/patologia , Análise de Sequência de DNA
11.
Genet Med ; 20(10): 1236-1245, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29323665

RESUMO

PURPOSE: We delineate the clinical spectrum and describe the histology in arterial tortuosity syndrome (ATS), a rare connective tissue disorder characterized by tortuosity of the large and medium-sized arteries, caused by mutations in SLC2A10. METHODS: We retrospectively characterized 40 novel ATS families (50 patients) and reviewed the 52 previously reported patients. We performed histology and electron microscopy (EM) on skin and vascular biopsies and evaluated TGF-ß signaling with immunohistochemistry for pSMAD2 and CTGF. RESULTS: Stenoses, tortuosity, and aneurysm formation are widespread occurrences. Severe but rare vascular complications include early and aggressive aortic root aneurysms, neonatal intracranial bleeding, ischemic stroke, and gastric perforation. Thus far, no reports unequivocally document vascular dissections or ruptures. Of note, diaphragmatic hernia and infant respiratory distress syndrome (IRDS) are frequently observed. Skin and vascular biopsies show fragmented elastic fibers (EF) and increased collagen deposition. EM of skin EF shows a fragmented elastin core and a peripheral mantle of microfibrils of random directionality. Skin and end-stage diseased vascular tissue do not indicate increased TGF-ß signaling. CONCLUSION: Our findings warrant attention for IRDS and diaphragmatic hernia, close monitoring of the aortic root early in life, and extensive vascular imaging afterwards. EM on skin biopsies shows disease-specific abnormalities.


Assuntos
Artérias/anormalidades , Proteínas Facilitadoras de Transporte de Glucose/genética , Hérnia Diafragmática/genética , Instabilidade Articular/genética , Síndrome do Desconforto Respiratório do Recém-Nascido/genética , Dermatopatias Genéticas/genética , Malformações Vasculares/genética , Adolescente , Adulto , Aorta/diagnóstico por imagem , Aorta/fisiopatologia , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Biópsia , Criança , Pré-Escolar , Fator de Crescimento do Tecido Conjuntivo/genética , Feminino , Hérnia Diafragmática/fisiopatologia , Humanos , Lactente , Instabilidade Articular/epidemiologia , Instabilidade Articular/fisiopatologia , Masculino , Mutação , Linhagem , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Pele/patologia , Dermatopatias Genéticas/epidemiologia , Dermatopatias Genéticas/fisiopatologia , Proteína Smad2/genética , Fator de Crescimento Transformador beta/genética , Malformações Vasculares/epidemiologia , Malformações Vasculares/fisiopatologia
12.
Neuropediatrics ; 49(2): 118-122, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29253910

RESUMO

Alexander disease (AD) is a leukodystrophy caused by heterozygous mutations in the gene encoding the glial fibrillary acidic protein (GFAP). Currently, de novo heterozygous missense mutations in the GFAP gene are identified in over 95% of patients with AD. However, patients with biopsy-proven AD have been reported in whom no GFAP mutation has been identified. We report identical twin boys presenting in infancy with seizures and developmental delay in whom MR appearances were suggestive of AD with the exception of an unusual, bilateral, arc of calcification at the frontal white-gray junction. Initial mutation screening of the GFAP gene did not identify a mutation. Whole exome sequencing in both brothers revealed a de novo heterozygous in-frame deletion of the whole of exon 5 of the GFAP gene. Mutations in the GFAP gene are thought to result in a toxic effect of mutant GFAP disrupting the formation of the normal intermediate filament network and resulting in Rosenthal fiber formation, which has hitherto not been linked to exonic scale copy number variants in GFAP. Further studies on mutation negative AD patients are warranted to determine whether a similar mechanism underlies their disease.


Assuntos
Doença de Alexander/genética , Éxons/genética , Deleção de Genes , Proteína Glial Fibrilar Ácida/genética , Doença de Alexander/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Análise Mutacional de DNA , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomógrafos Computadorizados
13.
Am J Hum Genet ; 90(2): 321-30, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22325361

RESUMO

Congenital stationary night blindness (CSNB) is a heterogeneous retinal disorder characterized by visual impairment under low light conditions. This disorder is due to a signal transmission defect from rod photoreceptors to adjacent bipolar cells in the retina. Two forms can be distinguished clinically, complete CSNB (cCSNB) or incomplete CSNB; the two forms are distinguished on the basis of the affected signaling pathway. Mutations in NYX, GRM6, and TRPM1, expressed in the outer plexiform layer (OPL) lead to disruption of the ON-bipolar cell response and have been seen in patients with cCSNB. Whole-exome sequencing in cCSNB patients lacking mutations in the known genes led to the identification of a homozygous missense mutation (c.1807C>T [p.His603Tyr]) in one consanguineous autosomal-recessive cCSNB family and a homozygous frameshift mutation in GPR179 (c.278delC [p.Pro93Glnfs(∗)57]) in a simplex male cCSNB patient. Additional screening with Sanger sequencing of 40 patients identified three other cCSNB patients harboring additional allelic mutations in GPR179. Although, immunhistological studies revealed Gpr179 in the OPL in wild-type mouse retina, Gpr179 did not colocalize with specific ON-bipolar markers. Interestingly, Gpr179 was highly concentrated in horizontal cells and Müller cell endfeet. The involvement of these cells in cCSNB and the specific function of GPR179 remain to be elucidated.


Assuntos
Exoma , Mutação , Miopia/genética , Cegueira Noturna/genética , Receptores Acoplados a Proteínas G/genética , Alelos , Animais , Eletrorretinografia/métodos , Oftalmopatias Hereditárias , Feminino , Doenças Genéticas Ligadas ao Cromossomo X , Heterogeneidade Genética , Técnicas de Genotipagem/métodos , Heterozigoto , Homozigoto , Humanos , Masculino , Camundongos , Fenótipo , Polimorfismo de Nucleotídeo Único , Estrutura Terciária de Proteína , Proteoglicanas/genética , Receptores de Glutamato Metabotrópico/genética , Retina/anormalidades , Canais de Cátion TRPM/genética
14.
PLoS Genet ; 8(11): e1002945, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144622

RESUMO

A homozygous mutational change in the Ataxia-Telangiectasia and RAD3 related (ATR) gene was previously reported in two related families displaying Seckel Syndrome (SS). Here, we provide the first identification of a Seckel Syndrome patient with mutations in ATRIP, the gene encoding ATR-Interacting Protein (ATRIP), the partner protein of ATR required for ATR stability and recruitment to the site of DNA damage. The patient has compound heterozygous mutations in ATRIP resulting in reduced ATRIP and ATR expression. A nonsense mutational change in one ATRIP allele results in a C-terminal truncated protein, which impairs ATR-ATRIP interaction; the other allele is abnormally spliced. We additionally describe two further unrelated patients native to the UK with the same novel, heterozygous mutations in ATR, which cause dramatically reduced ATR expression. All patient-derived cells showed defective DNA damage responses that can be attributed to impaired ATR-ATRIP function. Seckel Syndrome is characterised by microcephaly and growth delay, features also displayed by several related disorders including Majewski (microcephalic) osteodysplastic primordial dwarfism (MOPD) type II and Meier-Gorlin Syndrome (MGS). The identification of an ATRIP-deficient patient provides a novel genetic defect for Seckel Syndrome. Coupled with the identification of further ATR-deficient patients, our findings allow a spectrum of clinical features that can be ascribed to the ATR-ATRIP deficient sub-class of Seckel Syndrome. ATR-ATRIP patients are characterised by extremely severe microcephaly and growth delay, microtia (small ears), micrognathia (small and receding chin), and dental crowding. While aberrant bone development was mild in the original ATR-SS patient, some of the patients described here display skeletal abnormalities including, in one patient, small patellae, a feature characteristically observed in Meier-Gorlin Syndrome. Collectively, our analysis exposes an overlapping clinical manifestation between the disorders but allows an expanded spectrum of clinical features for ATR-ATRIP Seckel Syndrome to be defined.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Nanismo/genética , Transtornos do Crescimento , Micrognatismo , Proteínas Serina-Treonina Quinases , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Códon sem Sentido , Microtia Congênita , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Nanismo/patologia , Orelha/anormalidades , Orelha/patologia , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/patologia , Regulação da Expressão Gênica , Transtornos do Crescimento/genética , Transtornos do Crescimento/patologia , Heterozigoto , Humanos , Masculino , Microcefalia/genética , Microcefalia/patologia , Micrognatismo/genética , Micrognatismo/patologia , Osteocondrodisplasias/genética , Osteocondrodisplasias/patologia , Patela/anormalidades , Patela/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Splicing de RNA , Transdução de Sinais/genética
15.
Hum Mutat ; 34(1): 237-47, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23033313

RESUMO

OFD1, now recognized as a ciliopathy, is characterized by malformations of the face, oral cavity and digits, and is transmitted as an X-linked condition with lethality in males. Mutations in OFD1 also cause X-linked Joubert syndrome (JBTS10) and Simpson-Golabi-Behmel syndrome type 2 (SGBS2). We have studied 55 sporadic and six familial cases of suspected OFD1. Comprehensive mutation analysis in OFD1 revealed mutations in 37 female patients from 30 families; 22 mutations have not been previously described including two heterozygous deletions spanning OFD1 and neighbouring genes. Analysis of clinical findings in patients with mutations revealed that oral features are the most reliable diagnostic criteria. A first, detailed evaluation of brain MRIs from seven patients with cognitive defects illustrated extensive variability with the complete brain phenotype consisting of complete agenesis of the corpus callosum, large single or multiple interhemispheric cysts, striking cortical infolding of gyri, ventriculomegaly, mild molar tooth malformation and moderate to severe cerebellar vermis hypoplasia. Although the OFD1 gene apparently escapes X-inactivation, skewed inactivation was observed in seven of 14 patients. The direction of skewing did not correlate with disease severity, reinforcing the hypothesis that additional factors contribute to the extensive intrafamilial variability.


Assuntos
Deleção de Genes , Mutação , Síndromes Orofaciodigitais/genética , Proteínas/genética , Adolescente , Processamento Alternativo/genética , Sequência de Bases , Encéfalo/metabolismo , Encéfalo/patologia , Criança , Análise Mutacional de DNA , Éxons/genética , Saúde da Família , Feminino , Estudos de Associação Genética/métodos , Humanos , Lactente , Íntrons/genética , Imageamento por Ressonância Magnética , Masculino , Síndromes Orofaciodigitais/patologia , Linhagem , Inativação do Cromossomo X
16.
Hum Mutat ; 34(1): 111-21, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22829427

RESUMO

Autosomal recessive cutis laxa type I (ARCL type I) is characterized by generalized cutis laxa with pulmonary emphysema and/or vascular complications. Rarely, mutations can be identified in FBLN4 or FBLN5. Recently, LTBP4 mutations have been implicated in a similar phenotype. Studying FBLN4, FBLN5, and LTBP4 in 12 families with ARCL type I, we found bi-allelic FBLN5 mutations in two probands, whereas nine probands harbored biallelic mutations in LTBP4. FBLN5 and LTBP4 mutations cause a very similar phenotype associated with severe pulmonary emphysema, in the absence of vascular tortuosity or aneurysms. Gastrointestinal and genitourinary tract involvement seems to be more severe in patients with LTBP4 mutations. Functional studies showed that most premature termination mutations in LTBP4 result in severely reduced mRNA and protein levels. This correlated with increased transforming growth factor-beta (TGFß) activity. However, one mutation, c.4127dupC, escaped nonsense-mediated decay. The corresponding mutant protein (p.Arg1377Alafs(*) 27) showed reduced colocalization with fibronectin, leading to an abnormal morphology of microfibrils in fibroblast cultures, while retaining normal TGFß activity. We conclude that LTBP4 mutations cause disease through both loss of function and gain of function mechanisms.


Assuntos
Cútis Laxa/genética , Proteínas da Matriz Extracelular/genética , Proteínas de Ligação a TGF-beta Latente/genética , Mutação , Adolescente , Sequência de Bases , Western Blotting , Criança , Pré-Escolar , Consanguinidade , Cútis Laxa/complicações , Proteínas da Matriz Extracelular/metabolismo , Saúde da Família , Feminino , Expressão Gênica , Humanos , Lactente , Proteínas de Ligação a TGF-beta Latente/metabolismo , Masculino , Microscopia Eletrônica , Linhagem , Enfisema Pulmonar/complicações , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Pele/metabolismo , Pele/patologia , Pele/ultraestrutura , Adulto Jovem
17.
J Med Genet ; 48(4): 273-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21266384

RESUMO

BACKGROUND: Constitutional DICER1 mutations were recently reported to cause familial pleuropulmonary blastoma (PPB). AIM: To investigate the contribution and phenotypic spectrum of constitutional and somatic DICER1 mutations to cancer. METHODS AND RESULTS: The authors sequenced DICER1 in constitutional DNA from 823 unrelated patients with a variety of tumours and in 781 cancer cell lines. Constitutional DICER1 mutations were identified in 19 families including 11/14 with PPB, 2/3 with cystic nephroma, 4/7 with ovarian Sertoli-Leydig-type tumours, 1/243 with Wilms tumour (this patient also had a Sertoli-Leydig tumour), 1/1 with intraocular medulloepithelioma (this patient also had PPB), 1/86 with medulloblastoma/infratentorial primitive neuroectodermal tumour, and 1/172 with germ cell tumour. The inheritance was investigated in 17 families. DICER1 mutations were identified in 25 relatives: 17 were unaffected, one mother had ovarian Sertoli-Leydig tumour, one half-sibling had cystic nephroma, and six relatives had non-toxic thyroid cysts/goitre. Analysis of eight tumours from DICER1 mutation-positive patients showed universal retention of the wild-type allele. DICER1 truncating mutations were identified in 4/781 cancer cell lines; all were in microsatellite unstable lines and therefore unlikely to be driver mutations. CONCLUSION: Constitutional DICER1 haploinsufficiency predisposes to a broad range of tumours, making a substantial contribution to PPB, cystic nephroma and ovarian Sertoli-Leydig tumours, but a smaller contribution to other tumours. Most mutation carriers are unaffected, indicating that tumour risk is modest. The authors define the clinical contexts in which DICER1 mutation testing should be considered, the associated tumour risks, and the implications for at-risk individuals. They have termed this condition 'DICER1 syndrome'. ACCESSION NUMBERS: The cDNA Genbank accession number for the DICER1 sequence reported in this paper is NM_030621.2.


Assuntos
RNA Helicases DEAD-box/genética , Predisposição Genética para Doença , Neoplasias/genética , Ribonuclease III/genética , Linhagem Celular Tumoral , Mutação em Linhagem Germinativa , Haploinsuficiência , Humanos , Dados de Sequência Molecular , Neoplasias/diagnóstico , Análise de Sequência de DNA , Síndrome
19.
J Occup Environ Med ; 64(11): e677-e684, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35941740

RESUMO

OBJECTIVE: The aim of this study was to measure the association of working from home (WFH) with work productivity loss due to caregiving responsibilities or health problems during the COVID-19 pandemic. METHODS: We conducted an online survey of family/friend caregivers (n = 150 WFH/75 non-WFH) and patients (n = 95/91) who worked during the past 7 days in May and July 2020, respectively. Absenteeism and presenteeism were measured using the Valuation of Lost Productivity questionnaire. RESULTS: Working from home was associated with higher odds of absenteeism (odds ratio, 2.53; 95% confidence interval, 1.11 to 5.77) and presenteeism (2.79; 1.26 to 6.18) among caregivers and higher odds of presenteeism among patients (2.78; 1.13 to 6.84). However, among caregivers with absenteeism more than 0 days, WFH was significantly associated with fewer absent workdays. CONCLUSIONS: Working from home was not associated with overall absenteeism and presenteeism in caregivers or patients. Working from home allows a more flexible and inclusive workplace without impacting productivity, although further research is needed.


Assuntos
COVID-19 , Cuidadores , Humanos , COVID-19/epidemiologia , Pandemias , Estudos Transversais , Eficiência , Presenteísmo , Absenteísmo , Inquéritos e Questionários
20.
Eur J Hum Genet ; 30(1): 95-100, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34645992

RESUMO

White-Sutton syndrome (WHSUS) is a neurodevelopmental disorder caused by heterozygous loss-of-function variants in POGZ. Through the Deciphering Developmental Disorders study and clinical testing, we identified 12 individuals from 10 families with pathogenic or likely pathogenic variants in POGZ (eight de novo and two inherited). Most individuals had delayed development and/or intellectual disability. We analyzed the clinical findings in our series and combined it with data from 89 previously reported individuals. The results demonstrate WHSUS is associated with variable developmental delay or intellectual disability, increased risk of obesity, visual defects, craniofacial dysmorphism, sensorineural hearing loss, feeding problems, seizures, and structural brain malformations. Our series includes further individuals with rod-cone dystrophy, cleft lip and palate, congenital diaphragmatic hernia, and duplicated renal drainage system, suggesting these are rare complications of WHSUS. In addition, we describe an individual with a novel, de novo missense variant in POGZ and features of WHSUS. Our work further delineates the phenotypic spectrum of WHSUS highlighting the variable severity of this disorder and the observation of familial pathogenic POGZ variants.


Assuntos
Anormalidades Múltiplas/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Fenótipo , Transposases/genética , Anormalidades Múltiplas/patologia , Adolescente , Adulto , Criança , Pré-Escolar , Deficiências do Desenvolvimento/diagnóstico , Feminino , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Masculino , Mutação de Sentido Incorreto , Linhagem , Síndrome
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