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1.
Am J Hum Genet ; 104(6): 1040-1059, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31079900

RESUMO

The heterogeneous nuclear ribonucleoprotein (HNRNP) genes code for a set of RNA-binding proteins that function primarily in the spliceosome C complex. Pathogenic variants in these genes can drive neurodegeneration, through a mechanism involving excessive stress-granule formation, or developmental defects, through mechanisms that are not known. Here, we report four unrelated individuals who have truncating or missense variants in the same C-terminal region of hnRNPR and who have multisystem developmental defects including abnormalities of the brain and skeleton, dysmorphic facies, brachydactyly, seizures, and hypoplastic external genitalia. We further identified in the literature a fifth individual with a truncating variant. RNA sequencing of primary fibroblasts reveals that these HNRNPR variants drive significant changes in the expression of several homeobox genes, as well as other transcription factors, such as LHX9, TBX1, and multiple HOX genes, that are considered fundamental regulators of embryonic and gonad development. Higher levels of retained intronic HOX sequences and lost splicing events in the HOX cluster are observed in cells carrying HNRNPR variants, suggesting that impaired splicing is at least partially driving HOX deregulation. At basal levels, stress-granule formation appears normal in primary and transfected cells expressing HNRNPR variants. However, these cells reveal profound recovery defects, where stress granules fail to disassemble properly, after exposure to oxidative stress. This study establishes an essential role for HNRNPR in human development and points to a mechanism that may unify other "spliceosomopathies" linked to variants that drive multi-system congenital defects and are found in hnRNPs.

2.
J Med Genet ; 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287593

RESUMO

BACKGROUND: The clinical significance of 16p13.11 duplications remains controversial while frequently detected in patients with developmental delay (DD), intellectual deficiency (ID) or autism spectrum disorder (ASD). Previously reported patients were not or poorly characterised. The absence of consensual recommendations leads to interpretation discrepancy and makes genetic counselling challenging. This study aims to decipher the genotype-phenotype correlations to improve genetic counselling and patients' medical care. METHODS: We retrospectively analysed data from 16 013 patients referred to 12 genetic centers for DD, ID or ASD, and who had a chromosomal microarray analysis. The referring geneticists of patients for whom a 16p13.11 duplication was detected were asked to complete a questionnaire for detailed clinical and genetic data for the patients and their parents. RESULTS: Clinical features are mainly speech delay and learning disabilities followed by ASD. A significant risk of cardiovascular disease was noted. About 90% of the patients inherited the duplication from a parent. At least one out of four parents carrying the duplication displayed a similar phenotype to the propositus. Genotype-phenotype correlations show no impact of the size of the duplicated segment on the severity of the phenotype. However, NDE1 and miR-484 seem to have an essential role in the neurocognitive phenotype. CONCLUSION: Our study shows that 16p13.11 microduplications are likely pathogenic when detected in the context of DD/ID/ASD and supports an essential role of NDE1 and miR-484 in the neurocognitive phenotype. Moreover, it suggests the need for cardiac evaluation and follow-up and a large study to evaluate the aortic disease risk.

3.
Eur J Hum Genet ; 25(8): 1011-1014, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28589944

RESUMO

CHES (cerebellar hypoplasia with endosteal sclerosis) syndrome (OMIM#213002) associates hypomyelination, cerebellar atrophy, hypogonadism and hypodontia. So far, only five patients have been described. The condition is of neonatal onset. Patients have severe psychomotor delay and moderate to severe intellectual disability. Inheritance is assumed to be autosomal recessive due to recurrence in sibs, consanguinity of parents and absence of vertical transmission. CHES syndrome is reminiscent of 4H-leukodystrophy, a recessive-inherited affection due to variations in genes encoding subunits of the RNA polymerase III (POLR3A-POLR3B-POLR1C). POLR3B variants have been identified in one CHES patient. Here we report on a novel CHES patient, carrying compound heterozygous variations in POLR3B. This report confirms affiliation of CHES to POLR3-related disorders and suggests that CHES syndrome represents a severe form of 4H-leukodystrophy.


Assuntos
Ataxia Cerebelar/genética , Osteosclerose/genética , RNA Polimerase III/genética , Adolescente , Ataxia Cerebelar/diagnóstico , Heterozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Osteosclerose/diagnóstico
4.
J Med Genet ; 54(7): 479-488, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28119487

RESUMO

BACKGROUND: Cohesinopathies are rare neurodevelopmental disorders arising from a dysfunction in the cohesin pathway, which enables chromosome segregation and regulates gene transcription. So far, eight genes from this pathway have been reported in human disease. STAG1 belongs to the STAG subunit of the core cohesin complex, along with five other subunits. This work aimed to identify the phenotype ascribed to STAG1 mutations. METHODS: Among patients referred for intellectual disability (ID) in genetics departments worldwide, array-comparative genomic hybridisation (CGH), gene panel, whole-exome sequencing or whole-genome sequencing were performed following the local diagnostic standards. RESULTS: A mutation in STAG1 was identified in 17 individuals from 16 families, 9 males and 8 females aged 2-33 years. Four individuals harboured a small microdeletion encompassing STAG1; three individuals from two families had an intragenic STAG1 deletion. Six deletions were identified by array-CGH, one by whole-exome sequencing. Whole-exome sequencing found de novo heterozygous missense or frameshift STAG1 variants in eight patients, a panel of genes involved in ID identified a missense and a frameshift variant in two individuals. The 17 patients shared common facial features, with wide mouth and deep-set eyes. Four individuals had mild microcephaly, seven had epilepsy. CONCLUSIONS: We report an international series of 17 individuals from 16 families presenting with syndromic unspecific ID that could be attributed to a STAG1 deletion or point mutation. This first series reporting the phenotype ascribed to mutation in STAG1 highlights the importance of data sharing in the field of rare disorders.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Deficiência Intelectual/genética , Mutação/genética , Proteínas Nucleares/genética , Adulto , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Humanos , Lactente , Masculino , Linhagem , Fenótipo , Síndrome , Sequenciamento Completo do Exoma
5.
Hum Mutat ; 35(4): 478-85, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24470203

RESUMO

Mandibulofacial dysostosis, Guion-Almeida type (MFDGA) is a recently delineated multiple congenital anomalies/mental retardation syndrome characterized by the association of mandibulofacial dysostosis (MFD) with external ear malformations, hearing loss, cleft palate, choanal atresia, microcephaly, intellectual disability, oesophageal atresia (OA), congenital heart defects (CHDs), and radial ray defects. MFDGA emerges as a clinically recognizable entity, long underdiagnosed due to highly variable presentations. The main differential diagnoses are CHARGE and Feingold syndromes, oculoauriculovertebral spectrum, and other MFDs. EFTUD2, located on 17q21.31, encodes a component of the major spliceosome and is disease causing in MFDGA, due to heterozygous loss-of-function (LoF) mutations. Here, we describe a series of 36 cases of MFDGA, including 24 previously unreported cases, and we review the literature in order to delineate the clinical spectrum ascribed to EFTUD2 LoF. MFD, external ear anomalies, and intellectual deficiency occur at a higher frequency than microcephaly. We characterize the evolution of the facial gestalt at different ages and describe novel renal and cerebral malformations. The most frequent extracranial malformation in this series is OA, followed by CHDs and skeletal abnormalities. MFDGA is probably more frequent than other syndromic MFDs such as Nager or Miller syndromes. Although the wide spectrum of malformations complicates diagnosis, characteristic facial features provide a useful handle.


Assuntos
Anormalidades Múltiplas/patologia , Anus Imperfurado/patologia , Deformidades Congênitas da Mão/patologia , Perda Auditiva Bilateral/patologia , Deficiência Intelectual/patologia , Disostose Mandibulofacial/patologia , Microcefalia/patologia , Oftalmoplegia/patologia , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Ribonucleoproteína Nuclear Pequena U5/genética , Ribonucleoproteína Nuclear Pequena U5/metabolismo , Trombocitopenia/patologia , Anormalidades Múltiplas/genética , Anus Imperfurado/genética , Criança , Pré-Escolar , Diagnóstico Diferencial , Orelha Externa/patologia , Feminino , Deformidades Congênitas da Mão/genética , Haploinsuficiência , Perda Auditiva Bilateral/genética , Humanos , Lactente , Deficiência Intelectual/genética , Masculino , Disostose Mandibulofacial/genética , Microcefalia/genética , Mutação , Oftalmoplegia/genética , Fenótipo , Gravidez , Diagnóstico Pré-Natal , Trombocitopenia/genética
6.
J Med Genet ; 49(12): 737-46, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23188108

RESUMO

BACKGROUND: Oesophageal atresia (OA) and mandibulofacial dysostosis (MFD) are two congenital malformations for which the molecular bases of syndromic forms are being identified at a rapid rate. In particular, the EFTUD2 gene encoding a protein of the spliceosome complex has been found mutated in patients with MFD and microcephaly (MIM610536). Until now, no syndrome featuring both MFD and OA has been clearly delineated. RESULTS: We report on 10 cases presenting with MFD, eight of whom had OA, either due to de novo 17q21.31 deletions encompassing EFTUD2 and neighbouring genes or de novo heterozygous EFTUD2 loss-of-function mutations. No EFTUD2 deletions or mutations were found in a series of patients with isolated OA or isolated oculoauriculovertebral spectrum (OAVS). CONCLUSIONS: These data exclude a contiguous gene syndrome for the association of MFD and OA, broaden the spectrum of clinical features ascribed to EFTUD2 haploinsufficiency, define a novel syndromic OA entity, and emphasise the necessity of mRNA maturation through the spliceosome complex for global growth and within specific regions of the embryo during development. Importantly, the majority of patients reported here with EFTUD2 lesions were previously diagnosed with Feingold or CHARGE syndromes or presented with OAVS plus OA, highlighting the variability of expression and the wide range of differential diagnoses.


Assuntos
Atresia Esofágica/genética , Haploinsuficiência , Fatores de Alongamento de Peptídeos/genética , Adolescente , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 17 , Hibridização Genômica Comparativa , Facies , Feminino , Humanos , Lactente , Masculino , Fenótipo , Ribonucleoproteína Nuclear Pequena U5 , Síndrome
8.
Am J Med Genet A ; 143A(12): 1268-81, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17506106

RESUMO

The combination of pulmonary agenesis/dysgenesis/hypoplasia, microphthalmia/anophthalmia, and a diaphragmatic defect (agenesis or eventration) is a rare syndrome presumed to have an autosomal recessive mode of inheritance based on a report of affected siblings born to unaffected parents [Seller et al., 1996]. The condition is known as Spear syndrome and Matthew-Wood syndrome, although genetic heterogeneity cannot be ruled out. We report on eight patients with this condition including a living child, three sibs and three isolated cases. Most presented with fetal ultrasound findings of microphthalmia/anophthalmia, and diaphragmatic eventration/hernia and in five, cardiac abnormalities were also found. The earliest detection was at 20 weeks gestation. This is the second report of sibs affected with this condition, which supports an autosomal recessive mode of inheritance. We present the first and only reported living patient with this condition and expand the intrafamilial, interfamilial, and ethnic variability of this condition. We suggest changing the condition's name to PDAC to reflect the most important components of this condition.


Assuntos
Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Anoftalmia/patologia , Diafragma/anormalidades , Cardiopatias Congênitas , Pulmão/anormalidades , Anoftalmia/genética , Feminino , Genes Recessivos , Humanos , Recém-Nascido , Masculino
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