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1.
Am J Med Genet A ; 179(10): 2075-2082, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31361404

RESUMO

Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.

2.
Clin Genet ; 96(4): 366-370, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31309540

RESUMO

The canonical wingless (Wnt) and fibroblast growth factor (FGF) signaling pathways involving CTNNB1 and TBX4, respectively, are crucial for the regulation of human development. Perturbations of these pathways and disruptions from biological homeostasis have been associated with abnormal morphogenesis of multiple organs, including the lung. The aim of this study was to identify the underlying genetic cause of abnormal lung growth, pulmonary hypertension (PAH), severe microcephaly, and muscle spasticity in a full-term newborn, who died at 4 months of age due to progressively worsening PAH and respiratory failure. Family trio exome sequencing showed a de novo heterozygous nonsense c.1603C>T (p.Arg535*) variant in CTNNB1 and a paternally inherited heterozygous missense c.1198G>A (p.Glu400Lys) variant in TBX4, both predicted to be likely deleterious. We expand the phenotypic spectrum associated with CTNNB1 and TBX4 variants and indicate that they could act synergistically to produce a distinct more severe phenotype. Our findings further support a recently proposed complex compound inheritance model in lethal lung developmental diseases and the contention that dual molecular diagnoses can parsimoniously explain blended phenotypes.

3.
Proteomics Clin Appl ; 13(2): e1800135, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30548811

RESUMO

BACKGROUND: Progeria-like syndromes offer a unique insight into aging. Here the case of a boy affected with mandibuloacral dysplasia and compound heterozygous mutations in ZMPSTE24 is presented. METHODS: Capillary electrophoresis-mass spectroscopy is used for proteome analysis to analyze peptides previously found to be differentially regulated in chronic kidney disease (273 peptides defining the CKD273 classifier), coronary artery disease (238 peptides defining the CAD238 classifier), and aging (116 peptides defining the AGE116 classifier). RESULTS: No evidence of renal disease is identified. Although the boy has no overt cardiovascular disease other than a raised carotid intima media thickness relative to his age, a proteomic classifier for the diagnosis of coronary artery disease is mildly raised. The biological age based on the proteomic AGE116 classifier is 24 years compared to the chronological ages of 5 and 10 years. In contrast, a control group of healthy children has a significantly lower (p < 0.0001) calculated mean age of 13. CONCLUSION: Urinary proteomic analysis is effective in confirming advanced biological age and to identify early evidence of renal or cardiovascular damage. This case highlights the value of proteomic approaches in aging research and may represent a method for non-invasive monitoring of the effects of early aging.


Assuntos
Envelhecimento/genética , Doenças do Desenvolvimento Ósseo/genética , Anormalidades Craniofaciais/genética , Heterozigoto , Proteínas de Membrana/genética , Metaloendopeptidases/genética , Mutação , Proteômica , Criança , Pré-Escolar , Humanos
4.
Genome Res ; 29(2): 159-170, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30587507

RESUMO

Mutations that perturb normal pre-mRNA splicing are significant contributors to human disease. We used exome sequencing data from 7833 probands with developmental disorders (DDs) and their unaffected parents, as well as more than 60,000 aggregated exomes from the Exome Aggregation Consortium, to investigate selection around the splice sites and quantify the contribution of splicing mutations to DDs. Patterns of purifying selection, a deficit of variants in highly constrained genes in healthy subjects, and excess de novo mutations in patients highlighted particular positions within and around the consensus splice site of greater functional relevance. By using mutational burden analyses in this large cohort of proband-parent trios, we could estimate in an unbiased manner the relative contributions of mutations at canonical dinucleotides (73%) and flanking noncanonical positions (27%), and calculate the positive predictive value of pathogenicity for different classes of mutations. We identified 18 patients with likely diagnostic de novo mutations in dominant DD-associated genes at noncanonical positions in splice sites. We estimate 35%-40% of pathogenic variants in noncanonical splice site positions are missing from public databases.


Assuntos
Deficiências do Desenvolvimento/genética , Mutação , Sítios de Splice de RNA , Exoma , Humanos , Sequenciamento Completo do Exoma
5.
Eur J Hum Genet ; 26(11): 1611-1622, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30006632

RESUMO

Acrodysostosis (MIM 101800) is a dominantly inherited condition associating (1) skeletal features (short stature, facial dysostosis, and brachydactyly with cone-shaped epiphyses), (2) resistance to hormones and (3) possible intellectual disability. Acroscyphodysplasia (MIM 250215) is characterized by growth retardation, brachydactyly, and knee epiphyses embedded in cup-shaped metaphyses. We and others have identified PDE4D or PRKAR1A variants in acrodysostosis; PDE4D variants have been reported in three cases of acroscyphodysplasia. Our study aimed at reviewing the clinical and molecular findings in a cohort of 27 acrodysostosis and 5 acroscyphodysplasia cases. Among the acrodysostosis cases, we identified 9 heterozygous de novo PRKAR1A variants and 11 heterozygous PDE4D variants. The 7 patients without variants presented with symptoms of acrodysostosis (brachydactyly and cone-shaped epiphyses), but none had the characteristic facial dysostosis. In the acroscyphodysplasia cases, we identified 2 PDE4D variants. For 2 of the 3 negative cases, medical records revealed early severe infection, which has been described in some reports of acroscyphodysplasia. Subdividing our series of acrodysostosis based on the disease-causing gene, we confirmed genotype-phenotype correlations. Hormone resistance was consistently observed in patients carrying PRKAR1A variants, whereas no hormone resistance was observed in 9 patients with PDE4D variants. All patients with PDE4D variants shared characteristic facial features (midface hypoplasia with nasal hypoplasia) and some degree of intellectual disability. Our findings of PDE4D variants in two cases of acroscyphodysplasia support that PDE4D may be responsible for this severe skeletal dysplasia. We eventually emphasize the importance of some specific assessments in the long-term follow up, including cardiovascular and thromboembolic risk factors.

6.
Am J Med Genet A ; 176(4): 862-876, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29460469

RESUMO

In 2016, we described that missense variants in parts of exons 30 and 31 of CREBBP can cause a phenotype that differs from Rubinstein-Taybi syndrome (RSTS). Here we report on another 11 patients with variants in this region of CREBBP (between bp 5,128 and 5,614) and two with variants in the homologous region of EP300. None of the patients show characteristics typical for RSTS. The variants were detected by exome sequencing using a panel for intellectual disability in all but one individual, in whom Sanger sequencing was performed upon clinical recognition of the entity. The main characteristics of the patients are developmental delay (90%), autistic behavior (65%), short stature (42%), and microcephaly (43%). Medical problems include feeding problems (75%), vision (50%), and hearing (54%) impairments, recurrent upper airway infections (42%), and epilepsy (21%). Major malformations are less common except for cryptorchidism (46% of males), and cerebral anomalies (70%). Individuals with variants between bp 5,595 and 5,614 of CREBBP show a specific phenotype (ptosis, telecanthi, short and upslanted palpebral fissures, depressed nasal ridge, short nose, anteverted nares, short columella, and long philtrum). 3D face shape demonstrated resemblance to individuals with a duplication of 16p13.3 (the region that includes CREBBP), possibly indicating a gain of function. The other affected individuals show a less specific phenotype. We conclude that there is now more firm evidence that variants in these specific regions of CREBBP and EP300 result in a phenotype that differs from RSTS, and that this phenotype may be heterogeneous.

8.
Am J Hum Genet ; 101(1): 139-148, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28686853

RESUMO

We report 15 individuals with de novo pathogenic variants in WDR26. Eleven of the individuals carry loss-of-function mutations, and four harbor missense substitutions. These 15 individuals comprise ten females and five males, and all have intellectual disability with delayed speech, a history of febrile and/or non-febrile seizures, and a wide-based, spastic, and/or stiff-legged gait. These subjects share a set of common facial features that include a prominent maxilla and upper lip that readily reveal the upper gingiva, widely spaced teeth, and a broad nasal tip. Together, these features comprise a recognizable facial phenotype. We compared these features with those of chromosome 1q41q42 microdeletion syndrome, which typically contains WDR26, and noted that clinical features are consistent between the two subsets, suggesting that haploinsufficiency of WDR26 contributes to the pathology of 1q41q42 microdeletion syndrome. Consistent with this, WDR26 loss-of-function single-nucleotide mutations identified in these subjects lead to nonsense-mediated decay with subsequent reduction of RNA expression and protein levels. We derived a structural model of WDR26 and note that missense variants identified in these individuals localize to highly conserved residues of this WD-40-repeat-containing protein. Given that WDR26 mutations have been identified in ∼1 in 2,000 of subjects in our clinical cohorts and that WDR26 might be poorly annotated in exome variant-interpretation pipelines, we would anticipate that this disorder could be more common than currently appreciated.


Assuntos
Facies , Marcha/genética , Haploinsuficiência/genética , Deficiência Intelectual/genética , Proteínas/genética , Convulsões/genética , Sequência de Aminoácidos , Sequência de Bases , Pré-Escolar , Deleção Cromossômica , Feminino , Crescimento e Desenvolvimento/genética , Humanos , Deficiência Intelectual/complicações , Masculino , Mutação/genética , Proteínas/química , Estabilidade de RNA/genética , Convulsões/complicações , Síndrome
9.
Eur J Med Genet ; 60(2): 130-135, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27915094

RESUMO

Loss of function mutations in CTNNB1 have been reported in individuals with intellectual disability [MIM #615075] associated with peripheral spasticity, microcephaly and central hypotonia, suggesting a recognisable phenotype associated with haploinsufficiency for this gene. Trio based whole exome sequencing via the Deciphering Developmental Disorders (DDD) study has identified eleven further individuals with de novo loss of function mutations in CTNNB1. Here we report detailed phenotypic information on ten of these. We confirm the features that have been previously described and further delineate the skin and hair findings, including fair skin and fair and sparse hair with unusual patterning.


Assuntos
Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Microcefalia/genética , beta Catenina/genética , Adolescente , Adulto , Criança , Pré-Escolar , Deficiências do Desenvolvimento/fisiopatologia , Exoma/genética , Feminino , Haploinsuficiência/genética , Humanos , Deficiência Intelectual/fisiopatologia , Masculino , Microcefalia/fisiopatologia , Mutação , Fenótipo , Análise de Sequência de DNA
10.
J Pediatr Genet ; 5(3): 167-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27617159

RESUMO

The purpose of this study was to investigate the association of a chromosome 4:20 imbalance with osteoporosis in three related children. Bone biochemistry, bone turnover markers, and dual-energy X-ray absorptiometry (DXA) scanning were performed in all three cases and bone biopsy and histomorphometry in one. The chromosome imbalance was delineated by array comparative genomic hybridization (aCGH) and analyzed for candidate genes. A potential candidate gene within the deleted region is caspase-3, previously linked to low bone mineral density (BMD) in heterozygous mice thus caspase-3 activity was measured in cases and controls. Routine bone biochemistry and markers of bone turnover did not reveal any abnormality. DXA showed reduced total and lumbar spine bone mineral content. aCGH showed an 8 megabase (Mb) deletion of terminal chromosome 4q incorporating a region previously linked to low BMD and a 15 Mb duplication of terminal chromosome 20p. Bone biopsy showed a high bone turnover state, trabecularisation of cortical bone and numerous small osteoclasts coupled with normal bone formation. Basal serum caspase-3 activity was lower in cases compared with controls. We conclude that the early-onset osteoporosis with low basal levels of caspase-3 and abnormal osteoclasts is a feature of this chromosomal translocation. Further investigation of the role of the deleted and duplicated genes and especially caspase-3 is required.

11.
Hum Mol Genet ; 25(5): 927-35, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26740553

RESUMO

We present a generic, multidisciplinary approach for improving our understanding of novel missense variants in recently discovered disease genes exhibiting genetic heterogeneity, by combining clinical and population genetics with protein structural analysis. Using six new de novo missense diagnoses in TBL1XR1 from the Deciphering Developmental Disorders study, together with population variation data, we show that the ß-propeller structure of the ubiquitous WD40 domain provides a convincing way to discriminate between pathogenic and benign variation. Children with likely pathogenic mutations in this gene have severely delayed language development, often accompanied by intellectual disability, autism, dysmorphology and gastrointestinal problems. Amino acids affected by likely pathogenic missense mutations are either crucial for the stability of the fold, forming part of a highly conserved symmetrically repeating hydrogen-bonded tetrad, or located at the top face of the ß-propeller, where 'hotspot' residues affect the binding of ß-catenin to the TBLR1 protein. In contrast, those altered by population variation are significantly less likely to be spatially clustered towards the top face or to be at buried or highly conserved residues. This result is useful not only for interpreting benign and pathogenic missense variants in this gene, but also in other WD40 domains, many of which are associated with disease.


Assuntos
Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Heterogeneidade Genética , Mutação de Sentido Incorreto , Proteínas Nucleares/química , Receptores Citoplasmáticos e Nucleares/química , Proteínas Repressoras/química , beta Catenina/química , Sequência de Aminoácidos , Criança , Pré-Escolar , Deficiências do Desenvolvimento/metabolismo , Deficiências do Desenvolvimento/patologia , Feminino , Expressão Gênica , Genética Populacional , Humanos , Ligações de Hidrogênio , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Prognóstico , Ligação Proteica , Domínios Proteicos , Estrutura Secundária de Proteína , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Alinhamento de Sequência , beta Catenina/genética , beta Catenina/metabolismo
12.
Hum Mutat ; 36(4): 454-62, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25655089

RESUMO

Cornelia de Lange syndrome (CdLS) is characterized by facial dysmorphism, growth failure, intellectual disability, limb malformations, and multiple organ involvement. Mutations in five genes, encoding subunits of the cohesin complex (SMC1A, SMC3, RAD21) and its regulators (NIPBL, HDAC8), account for at least 70% of patients with CdLS or CdLS-like phenotypes. To date, only the clinical features from a single CdLS patient with SMC3 mutation has been published. Here, we report the efforts of an international research and clinical collaboration to provide clinical comparison of 16 patients with CdLS-like features caused by mutations in SMC3. Modeling of the mutation effects on protein structure suggests a dominant-negative effect on the multimeric cohesin complex. When compared with typical CdLS, many SMC3-associated phenotypes are also characterized by postnatal microcephaly but with a less distinctive craniofacial appearance, a milder prenatal growth retardation that worsens in childhood, few congenital heart defects, and an absence of limb deficiencies. While most mutations are unique, two unrelated affected individuals shared the same mutation but presented with different phenotypes. This work confirms that de novo SMC3 mutations account for ∼ 1%-2% of CdLS-like phenotypes.


Assuntos
Proteínas de Ciclo Celular/genética , Proteoglicanas de Sulfatos de Condroitina/genética , Proteínas Cromossômicas não Histona/genética , Síndrome de Lange/diagnóstico , Síndrome de Lange/genética , Heterozigoto , Mutação , Fenótipo , Alelos , Estudos de Coortes , Análise Mutacional de DNA , Exoma , Facies , Feminino , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino
13.
J Clin Endocrinol Metab ; 100(4): 1221-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25664603

RESUMO

CONTEXT: Ciliopathies are a group of rare conditions that present through a wide range of manifestations. Given the relative common occurrence of defects of the GH/IGF-I axis in children with short stature and growth retardation, the association between ciliopathies and these defects needs further attention. CASE: Our patient is a boy who was born at term and noted to have early growth retardation and weight gain within the first 18 months of life. Biochemical tests demonstrated low IGF-I but a normal peak GH on stimulation and an adequate increase in IGF-I on administration of recombinant human growth hormone (rhGH). A magnetic resonance imaging scan revealed pituitary hypoplasia and an ectopic posterior pituitary. His growth responded well to rhGH therapy. Subsequently he also developed a retinopathy of his rods and cones, metaphyseal dysplasia, and hypertension with renal failure requiring renal replacement therapy. Whole-exome sequencing demonstrated compound heterozygous mutations of IFT172, thus consistent with a ciliopathy. CONCLUSIONS: This is the first reported case of a child with a mutation in IFT172 who presented with growth retardation in early childhood and was initially managed as a case of functional GH deficiency that responded to rhGH therapy. This case highlights the importance of ciliary function in pituitary development and the link between early onset growth failure and ciliopathies.


Assuntos
Proteínas de Transporte/genética , Nanismo Hipofisário/genética , Hormônio do Crescimento Humano/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Adolescente , Criança , Pré-Escolar , Nanismo Hipofisário/tratamento farmacológico , Nanismo Hipofisário/metabolismo , Gráficos de Crescimento , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Lactente , Fator de Crescimento Insulin-Like I/metabolismo , Masculino
14.
Am J Med Genet A ; 167A(3): 461-75, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25604898

RESUMO

Type 2 collagen disorders encompass a diverse group of skeletal dysplasias that are commonly associated with orthopedic, ocular, and hearing problems. However, the frequency of many clinical features has never been determined. We retrospectively investigated the clinical, radiological, and genotypic data in a group of 93 patients with molecularly confirmed SEDC or a related disorder. The majority of the patients (80/93) had short stature, with radiological features of SEDC (n = 64), others having SEMD (n = 5), Kniest dysplasia (n = 7), spondyloperipheral dysplasia (n = 2), or Torrance-like dysplasia (n = 2). The remaining 13 patients had normal stature with mild SED, Stickler-like syndrome or multiple epiphyseal dysplasia. Over 50% of the patients had undergone orthopedic surgery, usually for scoliosis, femoral osteotomy or hip replacement. Odontoid hypoplasia was present in 56% (95% CI 38-74) and a correlation between odontoid hypoplasia and short stature was observed. Atlanto-axial instability, was observed in 5 of the 18 patients (28%, 95% CI 10-54) in whom flexion-extension films of the cervical spine were available; however, it was rarely accompanied by myelopathy. Myopia was found in 45% (95% CI 35-56), and retinal detachment had occurred in 12% (95% CI 6-21; median age 14 years; youngest age 3.5 years). Thirty-two patients complained of hearing loss (37%, 95% CI 27-48) of whom 17 required hearing aids. The ophthalmological features and possibly also hearing loss are often relatively frequent and severe in patients with splicing mutations. Based on clinical findings, age at onset and genotype-phenotype correlations in this cohort, we propose guidelines for the management and follow-up in this group of disorders.


Assuntos
Colágeno Tipo II/genética , Mutação , Osteocondrodisplasias/congênito , Fenótipo , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Radiografia , Adulto Jovem
15.
J Med Genet ; 51(10): 659-68, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25125236

RESUMO

BACKGROUND: Cornelia de Lange syndrome (CdLS) is a multisystem disorder with distinctive facial appearance, intellectual disability and growth failure as prominent features. Most individuals with typical CdLS have de novo heterozygous loss-of-function mutations in NIPBL with mosaic individuals representing a significant proportion. Mutations in other cohesin components, SMC1A, SMC3, HDAC8 and RAD21 cause less typical CdLS. METHODS: We screened 163 affected individuals for coding region mutations in the known genes, 90 for genomic rearrangements, 19 for deep intronic variants in NIPBL and 5 had whole-exome sequencing. RESULTS: Pathogenic mutations [including mosaic changes] were identified in: NIPBL 46 [3] (28.2%); SMC1A 5 [1] (3.1%); SMC3 5 [1] (3.1%); HDAC8 6 [0] (3.6%) and RAD21 1 [0] (0.6%). One individual had a de novo 1.3 Mb deletion of 1p36.3. Another had a 520 kb duplication of 12q13.13 encompassing ESPL1, encoding separase, an enzyme that cleaves the cohesin ring. Three de novo mutations were identified in ANKRD11 demonstrating a phenotypic overlap with KBG syndrome. To estimate the number of undetected mosaic cases we used recursive partitioning to identify discriminating features in the NIPBL-positive subgroup. Filtering of the mutation-negative group on these features classified at least 18% as 'NIPBL-like'. A computer composition of the average face of this NIPBL-like subgroup was also more typical in appearance than that of all others in the mutation-negative group supporting the existence of undetected mosaic cases. CONCLUSIONS: Future diagnostic testing in 'mutation-negative' CdLS thus merits deeper sequencing of multiple DNA samples derived from different tissues.


Assuntos
Síndrome de Lange/genética , Heterogeneidade Genética , Mosaicismo , Face/patologia , Estudos de Associação Genética , Humanos , Mutação , Fenótipo
16.
J Clin Endocrinol Metab ; 99(10): E2046-50, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25004247

RESUMO

CONTEXT: At least a third of the patients with pheochromocytoma (PCC) or paraganglioma (PGL) harbor an underlying germline mutation in a known PCC/PGL gene. Mutations in genes (SDHB, SDHD, SDHC, and SDHA) encoding a component of the tricarboxylic acid cycle, succinate dehydrogenase (SDH), are a major cause of inherited PCC and PGL. SDHB mutations are also, albeit less frequently, associated with inherited renal cell carcinoma. Inactivation of SDH and another tricarboxylic acid cycle component, fumarate hydratase (FH), have both been associated with abnormalities of cellular metabolism, responsible for the activation of hypoxic gene response pathways and epigenetic alterations (eg, DNA methylation). However, the clinical phenotype of germline mutations in SDHx genes and FH is usually distinct, with FH mutations classically associated with hereditary cutaneous and uterine leiomyomatosis and renal cell carcinoma, although recently an association with PCC/PGL has been reported. OBJECTIVE AND DESIGN: To identify potential novel PCC/PGL predisposition genes, we initially undertook exome resequencing studies in a case of childhood PCC, and subsequently FH mutation analysis in a further 71 patients with PCC, PGL, or head and neck PGL. RESULTS: After identifying a candidate FH missense mutation in the exome study, we then detected a further candidate missense mutation (p.Glu53Lys) by candidate gene sequencing. In vitro analyses demonstrated that both missense mutations (p.Cys434Tyr and p.Glu53Lys) were catalytically inactive. CONCLUSIONS: These findings 1) confirm that germline FH mutations may present, albeit rarely with PCC or PGL; and 2) extend the clinical phenotype associated with FH mutations to pediatric PCC.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Fumarato Hidratase/genética , Mutação em Linhagem Germinativa , Mutação de Sentido Incorreto , Feocromocitoma/genética , Adolescente , Idade de Início , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Paraganglioma/genética , Adulto Jovem
17.
Am J Med Genet A ; 161A(12): 2972-80, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24214728

RESUMO

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.


Assuntos
Anormalidades Múltiplas/genética , Hipotireoidismo Congênito/genética , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/genética , Deformidades Congênitas da Mão/genética , Deficiência Intelectual/genética , Complexo Repressor Polycomb 2/genética , Anormalidades Múltiplas/fisiopatologia , Adolescente , Criança , Pré-Escolar , Deleção Cromossômica , Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/fisiopatologia , Anormalidades Craniofaciais/complicações , Anormalidades Craniofaciais/fisiopatologia , Deficiências do Desenvolvimento , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Transtornos do Crescimento/complicações , Transtornos do Crescimento/fisiopatologia , Deformidades Congênitas da Mão/complicações , Deformidades Congênitas da Mão/fisiopatologia , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/fisiopatologia , Masculino , Mutação , Fenótipo , Síndrome de Sotos/genética , Síndrome de Sotos/fisiopatologia
18.
Am J Med Genet C Semin Med Genet ; 160C(3): 205-16, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22791362

RESUMO

From data collected via a large international collaborative study, we have constructed a growth chart for patients with molecularly confirmed congenital spondylo-epiphyseal dysplasia (SEDC) and other COL2A1 related dysplasias. The growth chart is based on longitudinal height measurements of 79 patients with glycine substitutions in the triple-helical domain of COL2A1. In addition, measurements of 27 patients with other molecular defects, such as arginine to cysteine substitutions, splice mutations, and mutations in the C-terminal propeptide have been plotted on the chart. Height of the patients progressively deviate from that of normal children: compared to normal WHO charts, the mean length/height is -2.6 SD at birth, -4.2 SD at 5 years, and -5.8 SD in adulthood. The mean adult height (male and female combined) of patients with glycine substitutions in the triple-helical region is 138.2 cm but there is a large variation. Patients with glycine to cysteine substitutions tend to cluster within the upper part of the chart, while patients with glycine to serine or valine substitutions are situated between +1 SD and -1 SD. Patients with carboxy-terminal glycine substitutions tend to be shorter than patients with amino-terminal substitutions, while patients with splice mutations are relatively tall. However, there are exceptions and specific mutations can have a strong or a relatively mild negative effect on growth. The observation of significant difference in adult height between affected members of the same family indicates that height remains a multifactorial trait even in the presence of a mutation with a strong dominant effect.


Assuntos
Colágeno Tipo II/genética , Gráficos de Crescimento , Mutação/genética , Osteocondrodisplasias/genética , Substituição de Aminoácidos/genética , Estatura/genética , Criança , Códon/genética , Colágeno Tipo II/química , Feminino , Humanos , Masculino , Osteocondrodisplasias/diagnóstico por imagem , Estrutura Secundária de Proteína , Processamento de RNA/genética , Radiografia , Adulto Jovem
19.
Am J Hum Genet ; 90(4): 740-5, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22464250

RESUMO

Acrodysostosis is a rare autosomal-dominant condition characterized by facial dysostosis, severe brachydactyly with cone-shaped epiphyses, and short stature. Moderate intellectual disability and resistance to multiple hormones might also be present. Recently, a recurrent mutation (c.1102C>T [p.Arg368*]) in PRKAR1A has been identified in three individuals with acrodysostosis and resistance to multiple hormones. After studying ten unrelated acrodysostosis cases, we report here de novo PRKAR1A mutations in five out of the ten individuals (we found c.1102C>T [p.Arg368(∗)] in four of the ten and c.1117T>C [p.Tyr373His] in one of the ten). We performed exome sequencing in two of the five remaining individuals and selected phosphodiesterase 4D (PDE4D) as a candidate gene. PDE4D encodes a class IV cyclic AMP (cAMP)-specific phosphodiesterase that regulates cAMP concentration. Exome analysis detected heterozygous PDE4D mutations (c.673C>A [p.Pro225Thr] and c.677T>C [p.Phe226Ser]) in these two individuals. Screening of PDE4D identified heterozygous mutations (c.568T>G [p.Ser190Ala] and c.1759A>C [p.Thr587Pro]) in two additional acrodysostosis cases. These mutations occurred de novo in all four cases. The four individuals with PDE4D mutations shared common clinical features, namely characteristic midface and nasal hypoplasia and moderate intellectual disability. Metabolic screening was normal in three of these four individuals. However, resistance to parathyroid hormone and thyrotropin was consistently observed in the five cases with PRKAR1A mutations. Finally, our study further supports the key role of the cAMP signaling pathway in skeletogenesis.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Disostoses/genética , Exoma/genética , Deficiência Intelectual/genética , Mutação , Osteocondrodisplasias/genética , Análise de Sequência de DNA , Adolescente , Adulto , Sequência de Bases , Criança , Pré-Escolar , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Hormônio Paratireóideo/metabolismo , Transdução de Sinais/genética , Tireotropina/metabolismo , Adulto Jovem
20.
Clin Dysmorphol ; 20(1): 1-10, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20733479

RESUMO

Auriculo-condylar syndrome (ACS, OMIM 602483) is an autosomal dominant condition with marked phenotypic variability. In some patients, the condition may be limited to the auricular deformity which can vary from auricular cleft, cupped helix to the 'question mark' ear, where there is constriction between the middle and lower thirds of the ear. The latter has also been reported in isolation. Other clinical features are; facial asymmetry, round faces with prominent cheeks, microstomia, micrognathia, dental malocclusion and hearing loss. Radiological findings include abnormalities of the temporomandibular joint and/or the mandibular condyle. We describe nine ACS patients (five familial, four singleton) with novel clinical signs including facial clefts, pre-auricular and cheek pits further delineating the features of this highly variable condition. Delayed diagnosis is a common feature suggesting that ACS is largely unrecognized and may be more common than the literature suggests.


Assuntos
Otopatias , Adulto , Criança , Pré-Escolar , Orelha/anormalidades , Orelha/diagnóstico por imagem , Otopatias/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Linhagem , Gravidez , Tomografia Computadorizada por Raios X , Adulto Jovem
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