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BACKGROUND: Sarcomas are diverse neoplasms with highly variable histological appearances in which diagnosis is often challenging and management options for metastatic/unresectable disease limited. Many sarcomas have distinctive molecular alterations, but the range of alterations is large, variable in type and rapidly increasing, meaning that testing by limited panels is unable to capture the broad spectrum of clinically pertinent genomic drivers required. Paired whole genome sequencing (WGS) in contrast allows comprehensive assessment of small variants, copy number and structural variants along with mutational signature analysis and germline testing. METHODS: Introduction of WGS as a diagnostic standard for all eligible patients with known or suspected soft tissue sarcoma over a 2-year period at a soft tissue sarcoma treatment centre. RESULTS: WGS resulted in a refinement in the diagnosis in 37% of cases, identification of a target for personalised therapy in 33% of cases, and a germline alteration in 4% of cases. CONCLUSION: Introduction of WGS poses logistical and training challenges, but offers significant benefits to this group of patients.
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BACKGROUND: Whole-genome sequencing (WGS) of cancers is becoming an accepted component of oncological care, and NHS England is currently rolling out WGS for all children with cancer. This approach was piloted during the 100,000 genomes (100 K) project. Here we share the experience of the East of England Genomic Medicine Centre (East-GMC), reporting the feasibility and clinical utility of centralised WGS for individual children locally. METHODS: Non-consecutive children with solid tumours were recruited into the pilot 100 K project at our Genomic Medicine Centre. Variant catalogues were returned for local scrutiny and appraisal at dedicated genomic tumour advisory boards with an emphasis on a detailed exploration of potential clinical value. RESULTS: Thirty-six children, representing one-sixth of the national 100 K cohort, were recruited through our Genomic Medicine Centre. The diagnoses encompassed 23 different solid tumour types and WGS provided clinical utility, beyond standard-of-care assays, by refining (2/36) or changing (4/36) diagnoses, providing prognostic information (8/36), defining pathogenic germline mutations (1/36) or revealing novel therapeutic opportunities (8/36). CONCLUSION: Our findings demonstrate the feasibility and clinical value of centralised WGS for children with cancer. WGS offered additional clinical value, especially in diagnostic terms. However, our experience highlights the need for local expertise in scrutinising and clinically interpreting centrally derived variant calls for individual children.
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Neoplasias , Medicina Estatal , Niño , Estudios de Factibilidad , Mutación de Línea Germinal , Humanos , Neoplasias/genética , Secuenciación Completa del GenomaRESUMEN
N-alpha-acetylation is a common co-translational protein modification that is essential for normal cell function in humans. We previously identified the genetic basis of an X-linked infantile lethal Mendelian disorder involving a c.109T>C (p.Ser37Pro) missense variant in NAA10, which encodes the catalytic subunit of the N-terminal acetyltransferase A (NatA) complex. The auxiliary subunit of the NatA complex, NAA15, is the dimeric binding partner for NAA10. Through a genotype-first approach with whole-exome or genome sequencing (WES/WGS) and targeted sequencing analysis, we identified and phenotypically characterized 38 individuals from 33 unrelated families with 25 different de novo or inherited, dominantly acting likely gene disrupting (LGD) variants in NAA15. Clinical features of affected individuals with LGD variants in NAA15 include variable levels of intellectual disability, delayed speech and motor milestones, and autism spectrum disorder. Additionally, mild craniofacial dysmorphology, congenital cardiac anomalies, and seizures are present in some subjects. RNA analysis in cell lines from two individuals showed degradation of the transcripts with LGD variants, probably as a result of nonsense-mediated decay. Functional assays in yeast confirmed a deleterious effect for two of the LGD variants in NAA15. Further supporting a mechanism of haploinsufficiency, individuals with copy-number variant (CNV) deletions involving NAA15 and surrounding genes can present with mild intellectual disability, mild dysmorphic features, motor delays, and decreased growth. We propose that defects in NatA-mediated N-terminal acetylation (NTA) lead to variable levels of neurodevelopmental disorders in humans, supporting the importance of the NatA complex in normal human development.
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Anomalías Múltiples/genética , Trastorno del Espectro Autista/genética , Predisposición Genética a la Enfermedad , Variación Genética , Discapacidad Intelectual/genética , Acetiltransferasa A N-Terminal/genética , Acetiltransferasa E N-Terminal/genética , Adolescente , Adulto , Línea Celular , Niño , Exones/genética , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Acetiltransferasa A N-Terminal/metabolismo , Acetiltransferasa E N-Terminal/metabolismo , Linaje , Fenotipo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMEN
Multiple primary tumors (MPTs) affect a substantial proportion of cancer survivors and can result from various causes, including inherited predisposition. Currently, germline genetic testing of MPT-affected individuals for variants in cancer-predisposition genes (CPGs) is mostly targeted by tumor type. We ascertained pre-assessed MPT individuals (with at least two primary tumors by age 60 years or at least three by 70 years) from genetics centers and performed whole-genome sequencing (WGS) on 460 individuals from 440 families. Despite previous negative genetic assessment and molecular investigations, pathogenic variants in moderate- and high-risk CPGs were detected in 67/440 (15.2%) probands. WGS detected variants that would not be (or were not) detected by targeted resequencing strategies, including low-frequency structural variants (6/440 [1.4%] probands). In most individuals with a germline variant assessed as pathogenic or likely pathogenic (P/LP), at least one of their tumor types was characteristic of variants in the relevant CPG. However, in 29 probands (42.2% of those with a P/LP variant), the tumor phenotype appeared discordant. The frequency of individuals with truncating or splice-site CPG variants and at least one discordant tumor type was significantly higher than in a control population (χ2 = 43.642; p ≤ 0.0001). 2/67 (3%) probands with P/LP variants had evidence of multiple inherited neoplasia allele syndrome (MINAS) with deleterious variants in two CPGs. Together with variant detection rates from a previous series of similarly ascertained MPT-affected individuals, the present results suggest that first-line comprehensive CPG analysis in an MPT cohort referred to clinical genetics services would detect a deleterious variant in about a third of individuals.
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Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Neoplasias Primarias Múltiples/genética , Adulto , Anciano , Biomarcadores de Tumor/genética , Femenino , Pruebas Genéticas/métodos , Mutación de Línea Germinal/genética , Humanos , Masculino , Persona de Mediana Edad , FenotipoRESUMEN
The study aimed at widening the clinical and genetic spectrum of ASXL3-related syndrome, a neurodevelopmental disorder, caused by truncating variants in the ASXL3 gene. In this international collaborative study, we have undertaken a detailed clinical and molecular analysis of 45 previously unpublished individuals with ASXL3-related syndrome, as well as a review of all previously published individuals. We have reviewed the rather limited functional characterization of pathogenic variants in ASXL3 and discuss current understanding of the consequences of the different ASXL3 variants. In this comprehensive analysis of ASXL3-related syndrome, we define its natural history and clinical evolution occurring with age. We report familial ASXL3 pathogenic variants, characterize the phenotype in mildly affected individuals and discuss nonpenetrance. We also discuss the role of missense variants in ASXL3. We delineate a variable but consistent phenotype. The most characteristic features are neurodevelopmental delay with consistently limited speech, significant neuro-behavioral issues, hypotonia, and feeding difficulties. Distinctive features include downslanting palpebral fissures, hypertelorism, tubular nose with a prominent nasal bridge, and low-hanging columella. The presented data will inform clinical management of individuals with ASXL3-related syndrome and improve interpretation of new ASXL3 sequence variants.
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Discapacidades del Desarrollo/genética , Predisposición Genética a la Enfermedad , Trastornos del Neurodesarrollo/genética , Factores de Transcripción/genética , Adolescente , Adulto , Niño , Preescolar , Discapacidades del Desarrollo/epidemiología , Discapacidades del Desarrollo/fisiopatología , Femenino , Variación Genética/genética , Humanos , Hipertelorismo/genética , Hipertelorismo/fisiopatología , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Masculino , Hipotonía Muscular/genética , Hipotonía Muscular/fisiopatología , Mutación/genética , Trastornos del Neurodesarrollo/epidemiología , Trastornos del Neurodesarrollo/fisiopatología , Fenotipo , Adulto JovenRESUMEN
Inherited retinal disease is a common cause of visual impairment and represents a highly heterogeneous group of conditions. Here, we present findings from a cohort of 722 individuals with inherited retinal disease, who have had whole-genome sequencing (n = 605), whole-exome sequencing (n = 72), or both (n = 45) performed, as part of the NIHR-BioResource Rare Diseases research study. We identified pathogenic variants (single-nucleotide variants, indels, or structural variants) for 404/722 (56%) individuals. Whole-genome sequencing gives unprecedented power to detect three categories of pathogenic variants in particular: structural variants, variants in GC-rich regions, which have significantly improved coverage compared to whole-exome sequencing, and variants in non-coding regulatory regions. In addition to previously reported pathogenic regulatory variants, we have identified a previously unreported pathogenic intronic variant in CHM in two males with choroideremia. We have also identified 19 genes not previously known to be associated with inherited retinal disease, which harbor biallelic predicted protein-truncating variants in unsolved cases. Whole-genome sequencing is an increasingly important comprehensive method with which to investigate the genetic causes of inherited retinal disease.
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Análisis Mutacional de ADN , Variación Genética/genética , Genoma Humano/genética , Enfermedades de la Retina/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Alelos , Secuencia de Bases , Coroideremia/genética , Etnicidad/genética , Exoma/genética , Femenino , Genes Recesivos/genética , Humanos , Intrones/genética , Masculino , Mutación , Enfermedades Raras/genéticaRESUMEN
Bromodomain PHD finger transcription factor (BPTF) is the largest subunit of nucleosome remodeling factor (NURF), a member of the ISWI chromatin-remodeling complex. However, the clinical consequences of disruption of this complex remain largely uncharacterized. BPTF is required for anterior-posterior axis formation of the mouse embryo and was shown to promote posterior neuroectodermal fate by enhancing Smad2-activated wnt8 expression in zebrafish. Here, we report eight loss-of-function and two missense variants (eight de novo and two of unknown origin) in BPTF on 17q24.2. The BPTF variants were found in unrelated individuals aged between 2.1 and 13 years, who manifest variable degrees of developmental delay/intellectual disability (10/10), speech delay (10/10), postnatal microcephaly (7/9), and dysmorphic features (9/10). Using CRISPR-Cas9 genome editing of bptf in zebrafish to induce a loss of gene function, we observed a significant reduction in head size of F0 mutants compared to control larvae. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and phospho-histone H3 (PH3) staining to assess apoptosis and cell proliferation, respectively, showed a significant increase in cell death in F0 mutants compared to controls. Additionally, we observed a substantial increase of the ceratohyal angle of the craniofacial skeleton in bptf F0 mutants, indicating abnormal craniofacial patterning. Taken together, our data demonstrate the pathogenic role of BPTF haploinsufficiency in syndromic neurodevelopmental anomalies and extend the clinical spectrum of human disorders caused by ablation of chromatin remodeling complexes.
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Anomalías Múltiples/genética , Antígenos Nucleares/genética , Anomalías Craneofaciales/genética , Regulación del Desarrollo de la Expresión Génica , Haploinsuficiencia/genética , Trastornos del Desarrollo del Lenguaje/genética , Microcefalia/genética , Proteínas del Tejido Nervioso/genética , Factores de Transcripción/genética , Anomalías Múltiples/patología , Adolescente , Animales , Antígenos Nucleares/metabolismo , Sistemas CRISPR-Cas , Proliferación Celular , Células Cultivadas , Niño , Preescolar , Ensamble y Desensamble de Cromatina , Estudios de Cohortes , Anomalías Craneofaciales/patología , Femenino , Edición Génica , Haploinsuficiencia/fisiología , Humanos , Trastornos del Desarrollo del Lenguaje/patología , Larva/genética , Larva/crecimiento & desarrollo , Masculino , Microcefalia/patología , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Neuronas/patología , Fenotipo , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Pez Cebra/genética , Pez Cebra/crecimiento & desarrolloRESUMEN
ACTB encodes ß-actin, an abundant cytoskeletal housekeeping protein. In humans, postulated gain-of-function missense mutations cause Baraitser-Winter syndrome (BRWS), characterized by intellectual disability, cortical malformations, coloboma, sensorineural deafness, and typical facial features. To date, the consequences of loss-of-function ACTB mutations have not been proven conclusively. We describe heterozygous ACTB deletions and nonsense and frameshift mutations in 33 individuals with developmental delay, apparent intellectual disability, increased frequency of internal organ malformations (including those of the heart and the renal tract), growth retardation, and a recognizable facial gestalt (interrupted wavy eyebrows, dense eyelashes, wide nose, wide mouth, and a prominent chin) that is distinct from characteristics of individuals with BRWS. Strikingly, this spectrum overlaps with that of several chromatin-remodeling developmental disorders. In wild-type mouse embryos, ß-actin expression was prominent in the kidney, heart, and brain. ACTB mRNA expression levels in lymphoblastic lines and fibroblasts derived from affected individuals were decreased in comparison to those in control cells. Fibroblasts derived from an affected individual and ACTB siRNA knockdown in wild-type fibroblasts showed altered cell shape and migration, consistent with known roles of cytoplasmic ß-actin. We also demonstrate that ACTB haploinsufficiency leads to reduced cell proliferation, altered expression of cell-cycle genes, and decreased amounts of nuclear, but not cytoplasmic, ß-actin. In conclusion, we show that heterozygous loss-of-function ACTB mutations cause a distinct pleiotropic malformation syndrome with intellectual disability. Our biological studies suggest that a critically reduced amount of this protein alters cell shape, migration, proliferation, and gene expression to the detriment of brain, heart, and kidney development.
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Anomalías Múltiples/genética , Actinas/genética , Discapacidades del Desarrollo/genética , Haploinsuficiencia/genética , Actinas/biosíntesis , Adolescente , Adulto , Anciano , Animales , Ciclo Celular/genética , Proliferación Celular/genética , Niño , Preescolar , Codón sin Sentido/genética , Coloboma/genética , Facies , Femenino , Mutación del Sistema de Lectura/genética , Eliminación de Gen , Humanos , Lactante , Recién Nacido , Discapacidad Intelectual/genética , Masculino , Malformaciones del Desarrollo Cortical/genética , Ratones , Interferencia de ARN , ARN Interferente Pequeño/genética , Adulto JovenRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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BACKGROUND: Primary hyperparathyroidism (PHPTH) is a common endocrine disorder and an estimated 10% of cases are hereditary, related to syndromes including; multiple endocrine neoplasia (MEN) type 1, MEN type 4, MEN2A and hereditary hyperparathyroidism-jaw tumour syndrome. Establishing the underlying genetic cause for PHPTH allows for personalized and cost-effective management. Familial hypocalicuric hypercalcaemia (FHH) is a benign disorder of hypercalcaemia associated with an inappropriately low urinary calcium excretion, which is quantified by the calcium creatinine clearance ratio (CCCR). Recent NHS England National Genomic Test Directory testing criteria for familial hyperparathyroidism state testing patients presenting with PHPTH and CCCR > 0.02 presenting (i) <35 years of age, or (ii) <45y with one of (a) multiglandular disease, or (b) hyperplasia on histology, or (c) ossifying fibroma(s) of the maxilla and/ or mandible, or (d) a family history of unexplained PHPTH. The testing criterion for FHH is a CCCR < 0.02. AIMS AND METHODS: A retrospective review of patients referred for genetic testing over a 4 year period for suspected hereditary HPTH was performed. Genetic analysis was performed by next-generation sequencing of the following genes; MEN1, CDC73, CASR, CDKN1A, CDKN1B, CDKN2B, CDKN2C, RET, GCM2, GNA11, and AP2S1 in NHS-accredited Regional Genetic laboratories. Aims of this study were to better define testing criteria for suspected hereditary PHPTH in a UK cohort. RESULTS: A total of 121 patients were included in this study (92 female) with a mean age of 41 years (SD 17). A pathogenic germline variant was identified in 16% (n = 19). A pathogenic variant was identified in the PHPTH genes CDC73 in a single patient and MEN1 in six patients (6% of total), in the FHH genes, CASR in 11 patients and AP2S1 in a single paediatric case (10% of total). A variant of uncertain significance (VUS) was identified in eight patients (6%) but over the course of this study familial segregation studies and computational analysis enabled re-classification of four of the variants, with two VUS's in the CASR gene being upgraded to likely pathogenic variants. Age at diagnosis and multiglandular disease as sole risk factors were not predictive of a pathogenic germline variant in this cohort but a positive family history was strongly predictive (P = .0002). A significant difference in the mean calcium creatinine clearance ratio (CCCR) in those patients with an identified CASR pathogenic variant versus those without (P = .0001) was demonstrated in this study. Thirty-three patients were aged over 50 years and the diagnostic rate of a pathogenic variant was 15.1% in those patients >50 years of age compared to 15.9% in those <50 years. Five patients >50 years and with a CCCR of <0.01, were diagnosed with a pathogenic variant in CASR. CONCLUSION: Family history was the strongest predictor of hereditary PHPTH in this cohort. This study has highlighted the importance of re-evaluating VUS's in order to inform patient management and enable appropriate genetic counselling. Finally, this study has demonstrated the need to consider genetic testing for PHPTH in patients of any age, particularly those with additional risk factors.
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Hipercalcemia , Hiperparatiroidismo Primario , Anciano , Niño , Femenino , Pruebas Genéticas , Humanos , Hipercalcemia/congénito , Hipercalcemia/genética , Hiperparatiroidismo Primario/genética , Recién Nacido , Estudios Retrospectivos , Reino UnidoRESUMEN
PURPOSE: Pathogenic variants in KAT6A have recently been identified as a cause of syndromic developmental delay. Within 2 years, the number of patients identified with pathogenic KAT6A variants has rapidly expanded and the full extent and variability of the clinical phenotype has not been reported. METHODS: We obtained data for patients with KAT6A pathogenic variants through three sources: treating clinicians, an online family survey distributed through social media, and a literature review. RESULTS: We identified 52 unreported cases, bringing the total number of published cases to 76. Our results expand the genotypic spectrum of pathogenic variants to include missense and splicing mutations. We functionally validated a pathogenic splice-site variant and identified a likely hotspot location for de novo missense variants. The majority of clinical features in KAT6A syndrome have highly variable penetrance. For core features such as intellectual disability, speech delay, microcephaly, cardiac anomalies, and gastrointestinal complications, genotype- phenotype correlations show that late-truncating pathogenic variants (exons 16-17) are significantly more prevalent. We highlight novel associations, including an increased risk of gastrointestinal obstruction. CONCLUSION: Our data expand the genotypic and phenotypic spectrum for individuals with genetic pathogenic variants in KAT6A and we outline appropriate clinical management.
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Discapacidades del Desarrollo/genética , Histona Acetiltransferasas/genética , Discapacidad Intelectual/genética , Adolescente , Adulto , Niño , Preescolar , Deleción Cromosómica , Discapacidades del Desarrollo/fisiopatología , Exoma/genética , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Lactante , Discapacidad Intelectual/fisiopatología , Masculino , Microcefalia/genética , Microcefalia/fisiopatología , Mutación , Fenotipo , Isoformas de Proteínas/genética , Adulto JovenRESUMEN
Brachyolmia is a skeletal dysplasia characterized by short spine-short stature, platyspondyly, and minor long bone abnormalities. We describe 18 patients, from different ethnic backgrounds and ages ranging from infancy to 19 years, with the autosomal recessive form, associated with PAPSS2. The main clinical features include disproportionate short stature with short spine associated with variable symptoms of pain, stiffness, and spinal deformity. Eight patients presented prenatally with short femora, whereas later in childhood their short-spine phenotype emerged. We observed the same pattern of changing skeletal proportion in other patients. The radiological findings included platyspondyly, irregular end plates of the elongated vertebral bodies, narrow disc spaces and short over-faced pedicles. In the limbs, there was mild shortening of femoral necks and tibiae in some patients, whereas others had minor epiphyseal or metaphyseal changes. In all patients, exome and Sanger sequencing identified homozygous or compound heterozygous PAPSS2 variants, including c.809G>A, common to white European patients. Bi-parental inheritance was established where possible. Low serum DHEAS, but not overt androgen excess was identified. Our study indicates that autosomal recessive brachyolmia occurs across continents and may be under-recognized in infancy. This condition should be considered in the differential diagnosis of short femora presenting in the second trimester.
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Enanismo/genética , Complejos Multienzimáticos/genética , Anomalías Musculoesqueléticas/genética , Osteocondrodisplasias/genética , Sulfato Adenililtransferasa/genética , Adolescente , Adulto , Niño , Preescolar , Enanismo/diagnóstico por imagen , Enanismo/fisiopatología , Femenino , Genes Recesivos/genética , Predisposición Genética a la Enfermedad , Homocigoto , Humanos , Lactante , Recién Nacido , Masculino , Anomalías Musculoesqueléticas/diagnóstico por imagen , Anomalías Musculoesqueléticas/fisiopatología , Osteocondrodisplasias/diagnóstico por imagen , Osteocondrodisplasias/fisiopatología , Linaje , Radiografía , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/fisiopatología , Secuenciación del Exoma , Adulto JovenRESUMEN
Charcot-Marie-Tooth disease (CMT) refers to a genetically heterogeneous group of disorders which cause a peripheral motor and sensory neuropathy. The overall prevalence is 1 in 2500 individuals. Mutations in the MFN2 gene are the commonest cause for the axonal (CMT2) type. We describe a Caucasian 5-year old girl affected by CMT2A since the age of 2 years. She presented with unsteady gait, in-turning of the feet and progressive foot deformities. Nerve conduction studies suggested an axonal neuropathy and molecular testing identified a previously reported pathogenic variant c.1090C > T, p.(Arg364Trp) in the MFN2 gene. This variant was also detected in a mosaic state in blood and saliva by Sanger sequencing in her subjectively healthy father. Next generation sequencing showed that the level of mosaicism was 21% in blood and 24% in saliva. A high recurrence risk was given because the father had proven somatic mosaicism and an affected child implying gonadal mosaicism. The parents were referred for pre-implantation genetic diagnosis. To the best of our knowledge, this is the first reported case of somatic mosaicism for MFN2. This study has important implications for genetic counselling in families with CMT2A.
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Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/patología , GTP Fosfohidrolasas/genética , Proteínas Mitocondriales/genética , Mosaicismo , Mutación Missense , Adulto , Preescolar , Relaciones Padre-Hijo , Femenino , Humanos , Masculino , Núcleo Familiar , Padres , Linaje , Fenotipo , Índice de Severidad de la EnfermedadRESUMEN
Genomic rearrangements involving AUTS2 (7q11.22) are associated with autism and intellectual disability (ID), although evidence for causality is limited. By combining the results of diagnostic testing of 49,684 individuals, we identified 24 microdeletions that affect at least one exon of AUTS2, as well as one translocation and one inversion each with a breakpoint within the AUTS2 locus. Comparison of 17 well-characterized individuals enabled identification of a variable syndromic phenotype including ID, autism, short stature, microcephaly, cerebral palsy, and facial dysmorphisms. The dysmorphic features were more pronounced in persons with 3'AUTS2 deletions. This part of the gene is shown to encode a C-terminal isoform (with an alternative transcription start site) expressed in the human brain. Consistent with our genetic data, suppression of auts2 in zebrafish embryos caused microcephaly that could be rescued by either the full-length or the C-terminal isoform of AUTS2. Our observations demonstrate a causal role of AUTS2 in neurocognitive disorders, establish a hitherto unappreciated syndromic phenotype at this locus, and show how transcriptional complexity can underpin human pathology. The zebrafish model provides a valuable tool for investigating the etiology of AUTS2 syndrome and facilitating gene-function analysis in the future.
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Exones/genética , Predisposición Genética a la Enfermedad , Discapacidad Intelectual/genética , Proteínas/química , Proteínas/genética , Eliminación de Secuencia/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Niño , Preescolar , Proteínas del Citoesqueleto , Facies , Femenino , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Fenotipo , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Supresión Genética , Síndrome , Factores de Transcripción , Adulto Joven , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/química , Proteínas de Pez Cebra/genéticaRESUMEN
Interstitial microdeletions of 20q chromosome are rare, only 17 patients have been reported in the literature to date. Among them, only six carried a proximal 20q11.21-q11.23 deletion, with a size ranging from 2.6 to 6.8 Mb. The existence of a 20q11.2 microdeletion syndrome has been proposed, based on five previously reported cases that displayed anomalies of the extremities, intellectual disability, feeding difficulties, craniofacial dysmorphism and variable malformations. To further characterize this syndrome, we report on six new patients with 20q11.2 microdeletions diagnosed by whole-genome array-based comparative genomic hybridization. These patient reports more precisely refined the phenotype and narrowed the minimal critical region involved in this syndrome. Careful clinical assessment confirms the distinctive clinical phenotype. The craniofacial dysmorphism consists of high forehead, frontal bossing, enophthalmos, and midface hypoplasia. We have identified a 1.62 megabase minimal critical region involved in this syndrome encompassing three genesGDF5, EPB41L1, andSAMHD1which are strong candidates for different aspects of the phenotype. These results support that 20q11.2 microdeletion syndrome is a new contiguous gene deletion syndrome with a recognizable phenotype.
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Anomalías Múltiples/diagnóstico , Anomalías Múltiples/genética , Deleción Cromosómica , Cromosomas Humanos Par 20 , Fenotipo , Adolescente , Niño , Preescolar , Aberraciones Cromosómicas , Puntos de Rotura del Cromosoma , Hibridación Genómica Comparativa , Facies , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Cariotipificación , Masculino , Síndrome , Adulto JovenRESUMEN
Wilms tumour (nephroblastoma) is a renal embryonal tumour that is frequently caused by constitutional variants in a small range of cancer predisposition genes. TRIM28 has recently been identified as one such gene. Previously, observational data strongly suggested a parent of origin effect, whereby Wilms tumour only occurred following maternal inheritance of a pathogenic genetic variant. However, here we report a child with bilateral Wilms tumour who had inherited a pathogenic TRIM28 variant from their father. This finding suggests that genetic counselling for paternally inherited pathogenic variants in TRIM28 should include discussion of a potential risk of Wilms tumour.
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Neoplasias Renales , Tumor de Wilms , Niño , Humanos , Masculino , Padre , Riñón/patología , Neoplasias Renales/genética , Neoplasias Renales/patología , Proteína 28 que Contiene Motivos Tripartito/genética , Tumor de Wilms/genética , Tumor de Wilms/patologíaRESUMEN
Clinical whole-genome sequencing (WGS) has been shown to deliver potential benefits to children with cancer and to alter treatment in high-risk patient groups. It remains unknown whether offering WGS to every child with suspected cancer can change patient management. We collected WGS variant calls and clinical and diagnostic information from 281 children (282 tumors) across two English units (n = 152 from a hematology center, n = 130 from a solid tumor center) where WGS had become a routine test. Our key finding was that variants uniquely attributable to WGS changed the management in ~7% (20 out of 282) of cases while providing additional disease-relevant findings, beyond standard-of-care molecular tests, in 108 instances for 83 (29%) cases. Furthermore, WGS faithfully reproduced every standard-of-care molecular test (n = 738) and revealed several previously unknown genomic features of childhood tumors. We show that WGS can be delivered as part of routine clinical care to children with suspected cancer and can change clinical management by delivering unexpected genomic insights. Our experience portrays WGS as a clinically impactful assay for routine practice, providing opportunities for assay consolidation and for delivery of molecularly informed patient care.
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Neoplasias , Secuenciación Completa del Genoma , Humanos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/diagnóstico , Niño , Masculino , Preescolar , Femenino , Adolescente , Lactante , Pruebas Genéticas/métodos , Genoma Humano/genética , Genómica/métodos , Recién NacidoRESUMEN
OBJECTIVES: Research studies have reported that about a third of individuals with phaeochromocytoma/paraganglioma (PPGL) have an inherited predisposition, although the frequency of specific mutations can vary between populations. We evaluated VHL, SDHB and SDHD mutation testing in cohorts of patients with non-syndromic PPGL and head and neck paraganglioma (HNPGL). DESIGN: Prospective, observational evaluation of NHS practice. PATIENTS: Individuals with PPGL/HNPGL referred to a supraregional genetics testing service over a 10-year period. MEASUREMENTS: Clinical (age, tumour site, malignancy, etc.), mutation frequencies and characteristics. RESULTS: A total of 501 probands with PPGL (n = 413) or HNPGL (n = 88) were studied. Thirty-one percent of patients with PPGL presented had a pathogenic mutation in SDHB, SDHD or VHL. Mutation detection rates were highest in those with a positive family history (62%), malignancy (53%), multiple tumours (33%) or PGL (44%). Twenty-eight percent of individuals with a single sporadic phaeochromocytoma had a mutation. Overall, 63% of patients with HNPGL had a mutation (92% of those with a family history, 89% of those with multicentric tumours and 34% of those with a single sporadic HNPGL). Penetrance was calculated in 121 SDHB mutation-positive probands and 187 of their mutation-positive relatives. Most relatives were asymptomatic and lifetime penetrance in non-proband SDHB mutation carriers was <50%. CONCLUSIONS: Practice-based evaluations of genetic testing in PPGL reveal high mutation detection rates. Although clinical criteria can be used to prioritize mutation testing, mutations were detected in 'low risk groups' indicating a need for comprehensive and inexpensive genetic testing strategies for PPGL and HNPGL.
Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Predisposición Genética a la Enfermedad/genética , Neoplasias de Cabeza y Cuello/genética , Paraganglioma/genética , Feocromocitoma/genética , Succinato Deshidrogenasa/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Pruebas Genéticas , Humanos , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Weaver syndrome, first described in 1974, is characterized by tall stature, a typical facial appearance, and variable intellectual disability. In 2011, mutations in the histone methyltransferase, EZH2, were shown to cause Weaver syndrome. To date, we have identified 48 individuals with EZH2 mutations. The mutations were primarily missense mutations occurring throughout the gene, with some clustering in the SET domain (12/48). Truncating mutations were uncommon (4/48) and only identified in the final exon, after the SET domain. Through analyses of clinical data and facial photographs of EZH2 mutation-positive individuals, we have shown that the facial features can be subtle and the clinical diagnosis of Weaver syndrome is thus challenging, especially in older individuals. However, tall stature is very common, reported in >90% of affected individuals. Intellectual disability is also common, present in ~80%, but is highly variable and frequently mild. Additional clinical features which may help in stratifying individuals to EZH2 mutation testing include camptodactyly, soft, doughy skin, umbilical hernia, and a low, hoarse cry. Considerable phenotypic overlap between Sotos and Weaver syndromes is also evident. The identification of an EZH2 mutation can therefore provide an objective means of confirming a subtle presentation of Weaver syndrome and/or distinguishing Weaver and Sotos syndromes. As mutation testing becomes increasingly accessible and larger numbers of EZH2 mutation-positive individuals are identified, knowledge of the clinical spectrum and prognostic implications of EZH2 mutations should improve.
Asunto(s)
Anomalías Múltiples/genética , Hipotiroidismo Congénito/genética , Anomalías Craneofaciales/genética , Trastornos del Crecimiento/genética , Deformidades Congénitas de la Mano/genética , Discapacidad Intelectual/genética , Complejo Represivo Polycomb 2/genética , Anomalías Múltiples/fisiopatología , Adolescente , Niño , Preescolar , Deleción Cromosómica , Hipotiroidismo Congénito/complicaciones , Hipotiroidismo Congénito/fisiopatología , Anomalías Craneofaciales/complicaciones , Anomalías Craneofaciales/fisiopatología , Discapacidades del Desarrollo , Proteína Potenciadora del Homólogo Zeste 2 , Femenino , Trastornos del Crecimiento/complicaciones , Trastornos del Crecimiento/fisiopatología , Deformidades Congénitas de la Mano/complicaciones , Deformidades Congénitas de la Mano/fisiopatología , Humanos , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/fisiopatología , Masculino , Mutación , Fenotipo , Síndrome de Sotos/genética , Síndrome de Sotos/fisiopatologíaRESUMEN
BACKGROUND: Neonates requiring early surgical intervention for major non-cardiac congenital anomalies are at high risk of adverse neurodevelopmental outcomes. Early recognition of potential neuro-developmental delay is critical to facilitate access to early childhood intervention services and therefore maximise the functional capabilities of these children. AIMS: This study aims to compare Bayley's Scales of Infant and Toddler Development (BSID-3) and the Paediatric Evaluation of Disability Inventory (PEDI) as early screening tools in predicting neuro-developmental disability across multiple domains. In addition, it looks at determining which pre, peri and post-operative risk factors lend themselves to more adverse outcomes. STUDY DESIGN: Retrospective cohort study. SUBJECTS: Neonates requiring surgical intervention at the Royal Children's Hospital from 2012 to 2018 who subsequently underwent neurodevelopmental assessment at 2 years of age. OUTCOME MEASURES: The main outcome was the relationship between performance on the PEDI compared with the BSID-3, in 2-year-olds following neonatal surgery. RESULTS: Parent -reported functional measures across all domains on PEDI strongly related to the more formal measures of cognition, language, and motor development assessed on BSID-3 (p < 0.05). CONCLUSIONS: The questionnaire-based PEDI tool could be considered a reliable replacement to the formal Bayley (BSID-3) scale in low-risk infants and provide a more accessible means of assessment where there are deficiencies in availability of suitably trained clinicians or limited resource centres.