Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Am J Med Genet A ; 179(8): 1556-1564, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31099476

RESUMO

Biallelic pathogenic variants in AARS2, a gene encoding the mitochondrial alanyl-tRNA synthetase, result in a spectrum of findings ranging from infantile cardiomyopathy to adult-onset progressive leukoencephalopathy. In this article, we present three unrelated individuals with novel compound heterozygous pathogenic AARS2 variants underlying diverse clinical presentations. Patient 1 is a 51-year-old man with adult-onset progressive cognitive, psychiatric, and motor decline and leukodystrophy. Patient 2 is a 34-year-old man with childhood-onset progressive tremor followed by the development of polyneuropathy, ataxia, and mild cognitive and psychiatric decline without leukodystrophy on imaging. Patient 3 is a 57-year-old woman with childhood-onset tremor and nystagmus which preceded dystonia, chorea, ataxia, depression, and cognitive decline marked by cerebellar atrophy and white matter disease. These cases expand the clinical heterogeneity of AARS2-related disorders, given that the first and third case represent some of the oldest known survivors of this disease, the second is adult-onset AARS2-related neurological decline without leukodystrophy, and the third is biallelic AARS2-related disorder involving a partial gene deletion.


Assuntos
Alanina-tRNA Ligase/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Fenótipo , Adulto , Alelos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética/métodos , Testes Genéticos , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/genética , Exame Neurológico
2.
Medicina (Kaunas) ; 55(5)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096651

RESUMO

Background and objectives: Loeys-Dietz syndrome 3, also known as aneurysms--osteoarthritis syndrome, is an autosomal dominant genetic connective tissue disease caused by pathogenic variants in SMAD3, a transcription factor involved in TGF-ß signaling. This disorder is characterized by early-onset osteoarthritis and arterial aneurysms. Common features include scoliosis, uvula abnormalities, striae, and velvety skin. Materials and Methods: The pathogenicity of a variant of uncertain significance in the SMAD3 gene was evaluated (variant c.220C > T) through personalized protein informatics and molecular studies. Results: The case of a 44-year-old male, who was originally presumed to have Marfan syndrome, is presented. An expanded gene panel determined the probable cause to be a variant in SMAD3, c.220C > T (p.R74W). His case was complicated by a history of stroke, but his phenotype was otherwise characteristic for Loeys-Dietz syndrome 3. Conclusion: This case emphasizes the importance of comprehensive genetic testing to evaluate patients for connective tissue disorders, as well as the potential benefit of utilizing a protein informatics platform for the assessment of variant pathogenicity.


Assuntos
Síndrome de Loeys-Dietz/genética , Proteína Smad3/análise , Proteína Smad3/genética , Adulto , Genômica/métodos , Humanos , Síndrome de Loeys-Dietz/sangue , Masculino , Fenótipo , Proteína Smad3/sangue
3.
Otol Neurotol ; 45(6): e468-e471, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38865723

RESUMO

OBJECTIVE: To report a fatal case of Susac syndrome in a congenitally deaf patient with a cochlear implant and a history of migraines, emphasizing the diagnostic challenges in patients with preexisting conditions. PATIENT: A 33-year-old male with congenital hearing loss, a cochlear implant, and chronic migraines who presented with mild subacute auditory disturbance and headaches that later progressed to severe encephalopathy. INTERVENTION: Explantation of a non-magnetic resonance imaging (MRI) compatible cochlear implant followed by MRI, fundoscopy, and the administration of immunosuppressive medications. MAIN OUTCOME MEASURES: Diagnosis was confirmed by characteristic MRI appearance and the presence of a hemi-retinal artery occlusion. RESULTS: After weeks of immunosuppressive treatment, the patient died of a global cerebral ischemic event of unknown origin. CONCLUSIONS: For patients with preexisting sensorineural hearing loss and cochlear implants, Susac syndrome poses a diagnostic challenge. Auditory disturbances in the absence of cochlear implant failure should prompt further evaluation for visual disturbances and encephalopathy. MRI and fundoscopy should be performed to detect other features of the disease.


Assuntos
Implantes Cocleares , Síndrome de Susac , Humanos , Masculino , Adulto , Síndrome de Susac/complicações , Síndrome de Susac/diagnóstico por imagem , Evolução Fatal , Imageamento por Ressonância Magnética , Surdez , Perda Auditiva Neurossensorial/etiologia , Implante Coclear , Transtornos de Enxaqueca/complicações , Oclusão da Artéria Retiniana/etiologia
4.
Cancer Genet ; 252-253: 107-110, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33493868

RESUMO

The titular member of the MAX network of proteins, MYC-associated factor X (MAX), serves an important regulatory function in transcription of E-box genes associated with cell proliferation, differentiation, and apoptosis. Wild type MAX dimerizes with both MYC and MAD, both of which are members of the MAX network, and can promote or repress cell functions as needed. However, pathogenic variants in MAX are known to upset this balance, leading to uncontrolled oncogenic activity and disease phenotypes such as paragangliomas and pheochromocytomas. We report a 58-year-old male and his 32-year-old daughter, both of which have a history of pheochromocytoma and the unique nonsense MAX variant c.271C>T (p.Q91X). These individuals were diagnosed with pheochromocytomas in their early twenties that were later removed through corrective surgery. The father now presents with recurrent symptoms of hypertension, hyperhidrosis, and headaches, which accompany new pheochromocytomas of his remaining adrenal gland. Pathogenicity of this MAX variant is proven through molecular modeling. The case of this father-daughter pair supports both heritability of pheochromocytoma and the paternal parent-of-origin effect for MAX pathogenic variants.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Predisposição Genética para Doença , Impressão Genômica , Feocromocitoma/genética , Adulto , Sequência de Aminoácidos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/química , Códon sem Sentido , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Linhagem
5.
Ophthalmic Genet ; 41(6): 563-569, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32940104

RESUMO

BACKGROUND: Autosomal Dominant Optic Atrophy (ADOA) is caused by mutations in the Optic Atrophy 1 Gene which disrupts the OPA1 protein. This disruption affects the normal function of the protein; impairs fusion of the mitochondrial inner membrane; and prevents normal OPA1 protein degradation. These events cause damage in retinal ganglion cells that could affect the patients with symptoms ranging from none to legally blind. MATERIALS AND METHODS: Our study identifies a missense variant mutation, c.1024 A > G (p.K342E), in OPA1 gene causing ADOA. Diagnosed clinically in three family members and the presence of this mutation was confirmed in two members by genetic testing. Pathogenic variants in OPA1 impact the secondary protein structure and function by causing non-conservative amino acid substitutions. We also modeled this mutation and compared it to the wild type using statistical mechanics. RESULTS AND CONCLUSIONS: The proband's pathogenic variant, c.1024 A > G (p.K342E), is located in the GTPase domain of OPA1 and causes changes in the protein structure by affecting the oligomerization pattern thus resulting in ADOA. Identifying the pathogenic potential of the missense mutations in the OPA1 gene using neoteric protein modeling techniques would help in the early detection of ADOA in patients who have family history of blindness. This action would help in providing early follow up, possible treatment in the future, and genetic counseling. Abbreviations: ADOA: Autosomal Dominant Optic Atrophy; CYCS: Caspase Activator Cytochrome C; OPA1: Optic Atrophy Gene 1; RGC: Retinal Ganglion Cells; VUS: Variant of Uncertain Significance.


Assuntos
GTP Fosfo-Hidrolases/genética , Mutação de Sentido Incorreto , Atrofia Óptica Autossômica Dominante/genética , Atrofia Óptica Autossômica Dominante/patologia , Adulto , Feminino , Genômica , Humanos , Masculino , Linhagem
6.
Case Rep Genet ; 2020: 3256539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32047678

RESUMO

BACKGROUND: The ATP-binding cassette, subfamily D, member 1 (ABCD1) protein is a peroxisomal half-transporter that allows for very long chain fatty acid (VLCFA) degradation. Pathogenic variants of ABCD1 cause VLCFAs to build up in various tissues and bodily fluids, resulting in a disorder called X-linked adrenoleukodystrophy (X-ALD). This disorder is most commonly marked by adrenocortical insufficiency and high VLCFA concentration, and has varying levels of neurological involvement depending on phenotype. For example, the Addison-only form of X-ALD has no neurological impact, while the cerebral form of X-ALD often causes severe sensory loss, motor function impairment, cognitive decline, and death. METHODS: A newly characterized and suspected pathogenic variant in ABCD1 cause VLCFAs to build up in various tissues and bodily fluids, resulting in a disorder called X-linked adrenoleukodystrophy (X-ALD). This disorder is most commonly marked by adrenocortical insufficiency and high VLCFA concentration, and has varying levels of neurological involvement depending on phenotype. For example, the Addison-only form of X-ALD has no neurological impact, while the cerebral form of X-ALD often causes severe sensory loss, motor function impairment, cognitive decline, and death. RESULTS: A case of adult onset adrenomyeloneuropathy (AMN) and a novel ABCD1 cause VLCFAs to build up in various tissues and bodily fluids, resulting in a disorder called X-linked adrenoleukodystrophy (X-ALD). This disorder is most commonly marked by adrenocortical insufficiency and high VLCFA concentration, and has varying levels of neurological involvement depending on phenotype. For example, the Addison-only form of X-ALD has no neurological impact, while the cerebral form of X-ALD often causes severe sensory loss, motor function impairment, cognitive decline, and death. CONCLUSIONS: Data fusion from multiple sources was combined in a comprehensive approach yielding an enriched assessment of the patient's disease and prognosis. Molecular modeling was performed on the variant to better characterize its clinical significance and confirm pathogenicity.

7.
Mol Genet Genomic Med ; 7(3): e566, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30693671

RESUMO

BACKGROUND: Transient receptor potential cation channel subfamily V member 4 (TRPV4) is an ion channel permeable to Ca2+ that is sensitive to physical, hormonal, and chemical stimuli. This protein is expressed in many cell types, including osteoclasts, chondrocytes, and sensory neurons. As such, pathogenic variants of this gene are associated with skeletal dysplasias and neuromuscular disorders. Pathogenesis of these phenotypes is not yet completely understood, but it is known that genotype-phenotype correlations for TRPV4 pathogenic variants often are not present. METHODS: Newly characterized, suspected pathogenic variant in TRPV4 was analyzed using protein informatics and personalized protein-level molecular studies, genomic exome analysis, and clinical study. RESULTS: This statement is demonstrated in the family of our proband, a 47-year-old female having the novel c.2401A>G (p.K801E) variant of TRPV4. We discuss the common symptoms between the proband, her father, and her daughter, and compare her phenotype to known TRPV4-associated skeletal dysplasias. CONCLUSIONS: Protein informatics and molecular modeling are used to confirm the pathogenicity of the unique TRPV4 variant found in this family. Multiple data were combined in a comprehensive manner to give complete overall perspective on the patient disease and prognosis.


Assuntos
Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto , Osteocondrodisplasias/genética , Fenótipo , Canais de Cátion TRPV/genética , Feminino , Humanos , Mutação com Perda de Função , Pessoa de Meia-Idade , Osteocondrodisplasias/patologia , Linhagem , Canais de Cátion TRPV/química , Canais de Cátion TRPV/metabolismo
8.
Bioinformatics ; 23(16): 2198-200, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17545183

RESUMO

UNLABELLED: OBO-Edit is an open source, platform-independent ontology editor developed and maintained by the Gene Ontology Consortium. Implemented in Java, OBO-Edit uses a graph-oriented approach to display and edit ontologies. OBO-Edit is particularly valuable for viewing and editing biomedical ontologies. AVAILABILITY: https://sourceforge.net/project/showfiles.php?group_id=36855.


Assuntos
Biologia Computacional/métodos , Documentação/métodos , Proteínas/genética , Proteínas/metabolismo , Interface Usuário-Computador , Gráficos por Computador , Armazenamento e Recuperação da Informação , Proteínas/classificação
9.
Artigo em Inglês | MEDLINE | ID: mdl-29700987

RESUMO

BACKGROUND: Haploinsufficiency of TAB2 is known to cause congenital heart defects and cardiomyopathy due to its important roles in cardiovascular tissue, both during development and through adult life. We report a sibling pair displaying adult-onset cardiomyopathy, hypermobility, and mild myopia. Our proband, a 39-year-old male, presents only with the above symptoms, while his 36-year-old sister was also notable for a ventricular septal defect in her infancy. METHODS: Whole-exome sequencing was utilized to identify the molecular basis of the phenotype found in two siblings. A molecular modeling technique that takes advantage of conformational sampling advances (Maxwell's demon molecular dynamics and Monte Carlo) were used to make a model of the mutant variant for comparative analytics to the wild-type. RESULTS: Exome sequencing revealed a novel, heterogeneous pathogenic variant in TAB2, c.1039 C>T (p.R347X), that was present in both individuals. This pathogenic variant removes just over half the residues from the TAB2 protein and severely impacts its functional ability, which we describe in detail. CONCLUSIONS: Analysis of the proband's family showed a history of cardiomyopathy, but no congenital heart defects or connective tissue disease. We highlight the heterogeneity in phenotype of TAB2 pathogenic variants and confirm the pathogenicity of this new variant through neoteric protein modeling techniques.

10.
Hum Genome Var ; 5: 18016, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29644085

RESUMO

Sensory ataxic neuropathy with dysarthria and ophthalmoparesis (SANDO) is a rare phenotype resulting from pathogenic variants of mitochondrial DNA polymerase gamma (POLG). We modeled a novel POLG variant, T599P, that causes the SANDO phenotype and another variant at the same residue, p.T599E, to observe their effect on protein function and confirm the pathogenicity of T599P. Through neoteric molecular modeling techniques, we show that changes at the T599 residue position introduce extra rigidity into the surrounding helix-loop-helix, which places steric pressure on nearby nucleotides. We also provide a clinical description of the T599P variant, which was found in a 42-year-old female proband. The proband presented a 1-year history of progressive gait instability, dysarthria and foot numbness. Her neurologic examination revealed ataxic dysarthria, restricted eye movements, head and palatal tremors, reduced lower limb reflexes, distal multimodal sensory loss and a wide, unsteady ataxic gait. Electromyography studies indicated a sensory neuropathy. Whole-exome sequencing was pursued after tests for infectious, inflammatory and paraneoplastic causes were negative.

11.
Mol Genet Genomic Med ; 6(6): 1229-1235, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30187681

RESUMO

BACKGROUND: Beta-galactosidase-1 (GLB1) is a lysosomal hydrolase that is responsible for breaking down specific glycoconjugates, particularly GM1 (monosialotetrahexosylganglioside). Pathogenic variants in GLB1 cause two different lysosomal storage disorders: GM1 gangliosidosis and mucopolysaccharidosis type IVB. In GM1 gangliosidosis, decreased ß-galactosidase-1 enzymatic activity leads to the accumulation of GM1 gangliosides, predominantly within the CNS. We present a 22-month-old proband with GM1 gangliosidosis type II (late-infantile form) in whom a novel homozygous in-frame deletion (c.1468_1470delAAC, p.Asn490del) in GLB1 was detected. METHODS: We used an experimental protein structure of ß-galactosidase-1 to generate a model of the p.Asn490del mutant and performed molecular dynamic simulations to determine whether this mutation leads to altered ligand positioning compared to the wild-type protein. In addition, residual mutant enzyme activity in patient leukocytes was evaluated using a fluorometric assay. RESULTS: Molecular dynamics simulations showed the deletion to alter the catalytic site leading to misalignment of the catalytic residues and loss of collective motion within the model. We predict this misalignment will lead to impaired catalysis of ß-galactosidase-1 substrates. Enzyme assays confirmed diminished GLB1 enzymatic activity (~3% of normal activity) in the proband. CONCLUSIONS: We have described a novel, pathogenic in-frame deletion of GLB1 in a patient with GM1 gangliosidosis type II.


Assuntos
Gangliosidose GM1/genética , Deleção de Genes , Simulação de Dinâmica Molecular , beta-Galactosidase/química , Humanos , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
12.
Clin Case Rep ; 6(1): 8-13, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29375828

RESUMO

This case report describes an individual with brain calcifications, cognitive decline, motor dysfunction, and hypocalcaemia. Exome sequencing revealed a previously reported variant in the CASR gene and a variant of uncertain significance in PDGFRB. The clinical phenotype is likely explained by the CASR variant, but we discuss how the PDGFRB variant could also participate in the phenotype.

13.
Case Rep Genet ; 2018: 6968395, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29682366

RESUMO

Chronic urticaria is a common condition characterized by recurrent hives lasting several weeks or months and is usually idiopathic. Approximately half of the individuals with chronic urticaria will present with episodes of angioedema that can be severe and debilitating. In this report, we describe a 47-year-old Hispanic male who presented initially for an evaluation of chronic hives following hospitalization due to hive-induced anaphylaxis. The individual had a history significant for urticaria and angioedema beginning in his early 30s. Interestingly, both the individual's 41-year-old sister and 12-year-old daughter were also affected with chronic urticaria and severe angioedema. Whole exome sequencing of the proband and several family members revealed a heterozygous variant of uncertain significance in exon 2 of TNFAIP3, denoted as c.65G>A (p.R22Q), in all affected members. Variants in TNFAIP3 have been associated with multiple autoimmune diseases, susceptibility to allergy and asthma, and periodic fever syndromes, suggesting that this variant could potentially play a role in disease.

14.
OMICS ; 10(2): 185-98, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16901225

RESUMO

The National Center for Biomedical Ontology is a consortium that comprises leading informaticians, biologists, clinicians, and ontologists, funded by the National Institutes of Health (NIH) Roadmap, to develop innovative technology and methods that allow scientists to record, manage, and disseminate biomedical information and knowledge in machine-processable form. The goals of the Center are (1) to help unify the divergent and isolated efforts in ontology development by promoting high quality open-source, standards-based tools to create, manage, and use ontologies, (2) to create new software tools so that scientists can use ontologies to annotate and analyze biomedical data, (3) to provide a national resource for the ongoing evaluation, integration, and evolution of biomedical ontologies and associated tools and theories in the context of driving biomedical projects (DBPs), and (4) to disseminate the tools and resources of the Center and to identify, evaluate, and communicate best practices of ontology development to the biomedical community. Through the research activities within the Center, collaborations with the DBPs, and interactions with the biomedical community, our goal is to help scientists to work more effectively in the e-science paradigm, enhancing experiment design, experiment execution, data analysis, information synthesis, hypothesis generation and testing, and understand human disease.


Assuntos
Pesquisa Biomédica/normas , National Institutes of Health (U.S.) , Software , Internet , Semântica , Estados Unidos
15.
Caring ; 21(7): 28-9, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12132181

RESUMO

Home care organizations today have realized the importance of market-driven strategic planning. The strategies developed are unique to the specific organization doing the planning after careful consideration of the characteristics of its marketplace. In addition to a competitive analysis that analyzes the capabilities of competing organizations, the agency must consider the external dynamics occurring within the home care community.


Assuntos
Gastos de Capital , Agências de Assistência Domiciliar/economia , Serviços de Assistência Domiciliar/economia , Técnicas de Planejamento , Competição Econômica , Administração Financeira/métodos , Setor de Assistência à Saúde/tendências , Objetivos Organizacionais , Estados Unidos
19.
Genome Biol ; 3(12): RESEARCH0083, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12537572

RESUMO

BACKGROUND: The recent completion of the Drosophila melanogaster genomic sequence to high quality and the availability of a greatly expanded set of Drosophila cDNA sequences, aligning to 78% of the predicted euchromatic genes, afforded FlyBase the opportunity to significantly improve genomic annotations. We made the annotation process more rigorous by inspecting each gene visually, utilizing a comprehensive set of curation rules, requiring traceable evidence for each gene model, and comparing each predicted peptide to SWISS-PROT and TrEMBL sequences. RESULTS: Although the number of predicted protein-coding genes in Drosophila remains essentially unchanged, the revised annotation significantly improves gene models, resulting in structural changes to 85% of the transcripts and 45% of the predicted proteins. We annotated transposable elements and non-protein-coding RNAs as new features, and extended the annotation of untranslated (UTR) sequences and alternative transcripts to include more than 70% and 20% of genes, respectively. Finally, cDNA sequence provided evidence for dicistronic transcripts, neighboring genes with overlapping UTRs on the same DNA sequence strand, alternatively spliced genes that encode distinct, non-overlapping peptides, and numerous nested genes. CONCLUSIONS: Identification of so many unusual gene models not only suggests that some mechanisms for gene regulation are more prevalent than previously believed, but also underscores the complex challenges of eukaryotic gene prediction. At present, experimental data and human curation remain essential to generate high-quality genome annotations.


Assuntos
Biologia Computacional/métodos , Drosophila melanogaster/genética , Eucromatina/genética , Genes de Insetos , Genoma , Animais , Bases de Dados Genéticas , Bases de Dados de Proteínas , Proteínas de Drosophila/genética , Humanos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa