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1.
Artigo em Inglês | MEDLINE | ID: mdl-33739604

RESUMO

OBJECTIVES: Genetic variant classification is a challenge in rare adult-onset disorders as in SCA-PRKCG (prior spinocerebellar ataxia type 14) with mostly private conventional mutations and nonspecific phenotype. We here propose a refined approach for clinicogenetic diagnosis by including protein modeling and provide for confirmed SCA-PRKCG a comprehensive phenotype description from a German multi-center cohort, including standardized 3D MR imaging. METHODS: This cross-sectional study prospectively obtained neurological, neuropsychological, and brain imaging data in 33 PRKCG variant carriers. Protein modeling was added as a classification criterion in variants of uncertain significance (VUS). RESULTS: Our sample included 25 cases confirmed as SCA-PRKCG (14 variants, thereof seven novel variants) and eight carriers of variants assigned as VUS (four variants) or benign/likely benign (two variants). Phenotype in SCA-PRKCG included slowly progressive ataxia (onset at 4-50 years), preceded in some by early-onset nonprogressive symptoms. Ataxia was often combined with action myoclonus, dystonia, or mild cognitive-affective disturbance. Inspection of brain MRI revealed nonprogressive cerebellar atrophy. As a novel finding, a previously not described T2 hyperintense dentate nucleus was seen in all SCA-PRKCG cases but in none of the controls. INTERPRETATION: In this largest cohort to date, SCA-PRKCG was characterized as a slowly progressive cerebellar syndrome with some clinical and imaging features suggestive of a developmental disorder. The observed non-ataxia movement disorders and cognitive-affective disturbance may well be attributed to cerebellar pathology. Protein modeling emerged as a valuable diagnostic tool for variant classification and the newly described T2 hyperintense dentate sign could serve as a supportive diagnostic marker of SCA-PRKCG.

2.
Sensors (Basel) ; 21(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669148

RESUMO

The usage of VR gear in mixed reality applications demands a high position and orientation accuracy of all devices to achieve a satisfying user experience. This paper investigates the system behaviour of the VR system HTC Vive Pro at a testing facility that is designed for the calibration of highly accurate positioning instruments like geodetic total stations, tilt sensors, geodetic gyroscopes or industrial laser scanners. Although the experiments show a high reproducibility of the position readings within a few millimetres, the VR system has systematic effects with magnitudes of several centimetres. A tilt of about 0.4∘ of the reference plane with respect to the horizontal plane was detected. Moreover, our results demonstrate that the tracking algorithm faces problems when several lighthouses are used.

3.
Genet Med ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531666

RESUMO

PURPOSE: The endoplasmic reticulum membrane complex (EMC) is a highly conserved, multifunctional 10-protein complex related to membrane protein biology. In seven families, we identified 13 individuals with highly overlapping phenotypes who harbor a single identical homozygous frameshift variant in EMC10. METHODS: Using exome, genome, and Sanger sequencing, a recurrent frameshift EMC10 variant was identified in affected individuals in an international cohort of consanguineous families. Multiple families were independently identified and connected via Matchmaker Exchange and internal databases. We assessed the effect of the frameshift variant on EMC10 RNA and protein expression and evaluated EMC10 expression in normal human brain tissue using immunohistochemistry. RESULTS: A homozygous variant EMC10 c.287delG (Refseq NM_206538.3, p.Gly96Alafs*9) segregated with affected individuals in each family, who exhibited a phenotypic spectrum of intellectual disability (ID) and global developmental delay (GDD), variable seizures and variable dysmorphic features (elongated face, curly hair, cubitus valgus, and arachnodactyly). The variant arose on two founder haplotypes and results in significantly reduced EMC10 RNA expression and an unstable truncated EMC10 protein. CONCLUSION: We propose that a homozygous loss-of-function variant in EMC10 causes a novel syndromic neurodevelopmental phenotype. Remarkably, the recurrent variant is likely the result of a hypermutable site and arose on distinct founder haplotypes.

6.
Am J Hum Genet ; 108(1): 115-133, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33308444

RESUMO

Signal peptide-CUB-EGF domain-containing protein 3 (SCUBE3) is a member of a small family of multifunctional cell surface-anchored glycoproteins functioning as co-receptors for a variety of growth factors. Here we report that bi-allelic inactivating variants in SCUBE3 have pleiotropic consequences on development and cause a previously unrecognized syndromic disorder. Eighteen affected individuals from nine unrelated families showed a consistent phenotype characterized by reduced growth, skeletal features, distinctive craniofacial appearance, and dental anomalies. In vitro functional validation studies demonstrated a variable impact of disease-causing variants on transcript processing, protein secretion and function, and their dysregulating effect on bone morphogenetic protein (BMP) signaling. We show that SCUBE3 acts as a BMP2/BMP4 co-receptor, recruits the BMP receptor complexes into raft microdomains, and positively modulates signaling possibly by augmenting the specific interactions between BMPs and BMP type I receptors. Scube3-/- mice showed craniofacial and dental defects, reduced body size, and defective endochondral bone growth due to impaired BMP-mediated chondrogenesis and osteogenesis, recapitulating the human disorder. Our findings identify a human disease caused by defective function of a member of the SCUBE family, and link SCUBE3 to processes controlling growth, morphogenesis, and bone and teeth development through modulation of BMP signaling.


Assuntos
Osso e Ossos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Deficiências do Desenvolvimento/metabolismo , Osteogênese/fisiologia , Transdução de Sinais/fisiologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 4/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Células HEK293 , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL
7.
Clin Genet ; 99(4): 513-518, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33354762

RESUMO

Congenital myopathies include a wide range of genetically determined disorders characterized by muscle weakness that usually manifest shortly after birth. To date, two different homozygous loss-of-function variants in the HACD1 gene have been reported to cause congenital myopathy. We identified three patients manifesting with neonatal-onset generalized muscle weakness and motor delay that carried three novel homozygous likely pathogenic HACD1 variants. The two of these changes (c.373_375+2delGAGGT and c.785-1G>T) were predicted to introduce splice site alterations, while one is a nonsense change (c.458G>A). The clinical presentation of our and the previously reported patients was comparable, including the temporally progressive improvement that seems to be characteristic of HACD1-related myopathy. Our findings conclusively confirm the implication of HACD1 in the pathogenesis of congenital myopathies, corroborate the main phenotypic features, and further define the genotypic spectrum of this genetic form of myopathy. Importantly, the genetic diagnosis of HACD1-related myopathy bears impactful prognostic value.

8.
Sci Data ; 7(1): 427, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33268827

RESUMO

The Year Of Polar Prediction (YOPP) dataset of the European Centre for Medium-Range Weather Forecasts (ECMWF) contains initial condition and forecast model output from the operational global, coupled numerical weather prediction system. The dataset has been created to support model forecast evaluation, predictability studies and model error analyses over polar areas, which are strongly affected by climate change with yet unknown feedbacks on global circulation. The dataset complements YOPP observation and modeling research activities that represent a key deliverable of the World Meteorological Organization's Polar Prediction Program. The dataset covers the period from mid-2017 until the end of the MOSAiC field campaign, expected for autumn 2020. Initial conditions and forecasts up to day-15 are included for the atmosphere and land surface for the entire period, and for ocean and sea-ice model components after June 2019. In addition, tendencies from model dynamics and individual physical processes are included for the first two forecast days. These are essential for characterizing the contribution of individual processes to model state evolution and, hence, for diagnosing sources of model error.

9.
Mov Disord ; 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33314351

RESUMO

BACKGROUND: Genetic stratification of Parkinson's disease (PD) patients facilitates gene-tailored research studies and clinical trials. The objective of this study was to describe the design of and the initial data from the Rostock International Parkinson's Disease (ROPAD) study, an epidemiological observational study aiming to genetically characterize ~10,000 participants. METHODS: Recruitment criteria included (1) clinical diagnosis of PD, (2) relative of participant with a reportable LRRK2 variant, or (3) North African Berber or Ashkenazi Jew. DNA analysis involved up to 3 successive steps: (1) variant (LRRK2) and gene (GBA) screening, (2) panel sequencing of 68 PD-linked genes, and (3) genome sequencing. RESULTS: Initial data based on the first 1360 participants indicated that the ROPAD enrollment strategy revealed a genetic diagnostic yield of ~14% among a PD cohort from tertiary referral centers. CONCLUSIONS: The ROPAD screening protocol is feasible for high-throughput genetic characterization of PD participants and subsequent prioritization for gene-focused research efforts and clinical trials. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC. on behalf of International Parkinson and Movement Disorder Society.

10.
Am J Med Genet A ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33166031

RESUMO

Schuurs-Hoeijmakers syndrome (SHS) is a rare syndrome involving a de novo variant in the PACS1 gene on chromosome 11q13. There are 36 individuals published in the literature so far, mostly diagnosed postnatally (34/36) after recognizing the typical facial features co-occurring with developmental delay, intellectual disability, and multiple malformations. Herein, we present one prenatal and 15 postnatal cases with the recurrent heterozygous pathogenic variant NM_018026.3:c.607C>T p.(Arg203Trp) in the PACS1 gene detected by exome sequencing. These 16 cases were identified by mining Centogene and the Hong Kong clinical genetic service databases. Collectively, the 49 postnatally diagnosed individuals present with typical facial features and developmental delay, while the three prenatally diagnosed individuals present with multiple congenital anomalies. In the current study, the use of exome sequencing as an unbiased diagnostic tool aided the diagnosis of SHS (pre- and postnatally). The identification of additional cases with SHS add to the current understanding of the clinical phenotype associated with pathogenic PACS1 variants. Databases combining clinical and genetic information are helpful for the study of rare diseases.

11.
Clin Genet ; 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33131077

RESUMO

We describe an X-linked syndrome in 13 male patients from a single family with three generations affected. Patients presented prenatally or during the neonatal period with intrauterine growth retardation, ventriculomegaly, hydrocephalus, hypotonia, congenital heart defects, hypospadias, and severe neurodevelopmental delay. The disease is typically fatal during infancy, mainly due to sepsis (pneumonias). Female carriers are asymptomatic. We performed genome sequencing in four individuals and identified a unique candidate variant in the OTUD5 gene (NM_017602.3:c.598G > A, p.Glu200Lys). The variant cosegregated with the disease in 10 tested individuals. OTUD5 was considered as a candidate gene based on two previous missense variants detected in patients with intellectual disability. In conclusion, we define a syndrome associated with OTUD5 defects and add compelling evidence of genotype-phenotype association. This finding ended the long diagnostic odyssey of this family.

12.
Ann Neurol ; 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33236446

RESUMO

OBJECTIVE: To identify a monogenic cause of early-onset, generalized dystonia. METHODS: Genome-wide linkage analysis, exome and Sanger sequencing, clinical neurological examination, brain MRI, and protein expression studies in skin fibroblasts from patients. RESULTS: We identified a heterozygous variant, c.388G>A, p.Gly130Arg in the Eukaryotic Translation Initiation Factor 2 Alpha Kinase 2 (EIF2AK2) gene, segregating with early-onset isolated generalized dystonia in five patients of a Taiwanese family. EIF2AK2 sequencing in 191 unrelated patients with unexplained dystonia yielded two unrelated Caucasian patients with an identical heterozygous c.388G>A, p.Gly130Arg variant, occurring de novo in one case, another patient carrying a different heterozygous variant, c.413G>C, p.Gly138Ala, and one last patient, born from consanguineous parents, carrying a third, homozygous variant c.95A>C, p.Asn32Thr. These three missense variants are absent from gnomAD, and are located in functional domains of the encoded protein. In three patients, additional neurological manifestations were present, including intellectual disability and spasticity. EIF2AK2 encodes a kinase (PKR) that phosphorylates the Eukaryotic Translation Initiation Factor 2 Alpha (eIF2α), which orchestrates the cellular stress response. Our expression studies showed abnormally enhanced activation of the cellular stress response, monitored by PKR-mediated phosphorylation of eIF2α, in fibroblasts from patients with EIF2AK2 variants. Intriguingly, PKR can also be regulated by PRKRA, the product of another gene causing monogenic dystonia. INTERPRETATION: We identified EIF2AK2 variants implicated in early-onset generalized dystonia, which can be dominantly or recessively inherited, or occur de novo. Our findings provide direct evidence for a key role of a dysfunctional eIF2α pathway in the pathogenesis of dystonia. This article is protected by copyright. All rights reserved.

13.
J Am Soc Nephrol ; 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020172

RESUMO

BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) are one of the most common malformations identified in the fetal stage. Bilateral renal agenesis (BRA) represents the most severe and fatal form of CAKUT. Only three genes have been confirmed to have a causal role in humans (ITGA8, GREB1L, and FGF20). METHODS: Genome sequencing within a diagnostic setting and combined data repository analysis identified a novel gene. RESULTS: Two patients presented with BRA, detected during the prenatal period, without additional recognizable malformations. They had parental consanguinity and similarly affected, deceased siblings, suggesting autosomal recessive inheritance. Evaluation of homozygous regions in patient 1 identified a novel, nonsense variant in GFRA1 (NM_001348097.1:c.676C>T, p.[Arg226*]). We identified 184 patients in our repository with renal agenesis and analyzed their exome/genome data. Of these 184 samples, 36 were from patients who presented with isolated renal agenesis. Two of them had loss-of-function variants in GFRA1. The second patient was homozygous for a frameshift variant (NM_001348097.1:c.1294delA, p.[Thr432Profs*13]). The GFRA1 gene encodes a receptor on the Wolffian duct that regulates ureteric bud outgrowth in the development of a functional renal system, and has a putative role in the pathogenesis of Hirschsprung disease. CONCLUSIONS: These findings strongly support the causal role of GFRA1-inactivating variants for an autosomal recessive, nonsyndromic form of BRA. This knowledge will enable early genetic diagnosis and better genetic counseling for families with BRA.

16.
NPJ Genom Med ; 5: 44, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083013

RESUMO

We implemented a collaborative diagnostic program in Lahore (Pakistan) aiming to establish the genetic diagnosis, and to asses diagnostic yield and clinical impact in patients with suspected genetic diseases. Local physicians ascertained pediatric patients who had no previous access to genetic testing. More than 1586 genetic tests were performed in 1019 individuals (349 index cases, 670 relatives). Most frequently performed tests were exome/genome sequencing (ES/GS, 284/78 index cases) and specific gene panels (55 index cases). In 61.3% of the patients (n = 214) a genetic diagnosis was established based on pathogenic and likely pathogenic variants. Diagnostic yield was higher in consanguineous families (60.1 vs. 39.5%). In 27 patients, genetic diagnosis relied on additional biochemical testing, allowing rapid assessment of the functional effect of the variants. Remarkably, the genetic diagnosis had a direct impact on clinical management. Most relevant consequences were therapy related such as initiation of the appropriated treatment in a timely manner in 51.9% of the patients (n = 111). Finally, we report 12 candidate genes among 66 cases with no genetic diagnosis. Importantly, three of these genes were validated as 'diagnostic' genes given the strong evidence supporting causality derived from our data repository (CAP2-dilated cardiomyopathy, ITFG2-intellectual disability and USP53-liver cholestasis). The high diagnostic yield, clinical impact, and research findings demonstrate the utility of genomic testing, especially when used as first-line genetic test. For patients with suspected genetic diseases from resource-limited regions, ES can be considered as the test of choice to achieve genetic diagnosis.

17.
Eur J Hum Genet ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901138

RESUMO

Trafficking protein particle (TRAPP) complexes, which include the TRAPPC4 protein, regulate membrane trafficking between lipid organelles in a process termed vesicular tethering. TRAPPC4 was recently implicated in a recessive neurodevelopmental condition in four unrelated families due to a shared c.454+3A>G splice variant. Here, we report 23 patients from 17 independent families with an early-infantile-onset neurodegenerative presentation, where we also identified the homozygous variant hg38:11:119020256 A>G (NM_016146.5:c.454+3A>G) in TRAPPC4 through exome or genome sequencing. No other clinically relevant TRAPPC4 variants were identified among any of over 10,000 patients with neurodevelopmental conditions. We found the carrier frequency of TRAPPC4 c.454+3A>G was 2.4-5.4 per 10,000 healthy individuals. Affected individuals with the homozygous TRAPPC4 c.454+3A>G variant showed profound psychomotor delay, developmental regression, early-onset epilepsy, microcephaly and progressive spastic tetraplegia. Based upon RNA sequencing, the variant resulted in partial exon 3 skipping and generation of an aberrant transcript owing to use of a downstream cryptic splice donor site, predicting a premature stop codon and nonsense mediated decay. These data confirm the pathogenicity of the TRAPPC4 c.454+3A>G variant, and refine the clinical presentation of TRAPPC4-related encephalopathy.

18.
Nat Commun ; 11(1): 4589, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917887

RESUMO

Mandibuloacral dysplasia syndromes are mainly due to recessive LMNA or ZMPSTE24 mutations, with cardinal nuclear morphological abnormalities and dysfunction. We report five homozygous null mutations in MTX2, encoding Metaxin-2 (MTX2), an outer mitochondrial membrane protein, in patients presenting with a severe laminopathy-like mandibuloacral dysplasia characterized by growth retardation, bone resorption, arterial calcification, renal glomerulosclerosis and severe hypertension. Loss of MTX2 in patients' primary fibroblasts leads to loss of Metaxin-1 (MTX1) and mitochondrial dysfunction, including network fragmentation and oxidative phosphorylation impairment. Furthermore, patients' fibroblasts are resistant to induced apoptosis, leading to increased cell senescence and mitophagy and reduced proliferation. Interestingly, secondary nuclear morphological defects are observed in both MTX2-mutant fibroblasts and mtx-2-depleted C. elegans. We thus report the identification of a severe premature aging syndrome revealing an unsuspected link between mitochondrial composition and function and nuclear morphology, establishing a pathophysiological link with premature aging laminopathies and likely explaining common clinical features.


Assuntos
Acro-Osteólise/metabolismo , Predisposição Genética para Doença/genética , Lipodistrofia/metabolismo , Mandíbula/anormalidades , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Acro-Osteólise/diagnóstico por imagem , Acro-Osteólise/genética , Acro-Osteólise/patologia , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Animais , Apoptose , Caenorhabditis elegans , Proliferação de Células , Criança , Regulação para Baixo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Genótipo , Homozigoto , Humanos , Lipodistrofia/diagnóstico por imagem , Lipodistrofia/genética , Lipodistrofia/patologia , Masculino , Mandíbula/diagnóstico por imagem , Proteínas de Membrana/genética , Metaloendopeptidases , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas Mitocondriais/genética , Mutação , Fenótipo , Pele , Sequenciamento Completo do Genoma
19.
Materials (Basel) ; 13(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731434

RESUMO

The contour scan strategies in laser powder bed fusion (LPBF) of Ti-6Al-4V were studied at the coupon level. These scan strategies determined the surface qualities and subsurface residual stresses. The correlations to these properties were identified for an optimization of the LPBF processing. The surface roughness and the residual stresses in build direction were linked: combining high laser power and high scan velocities with at least two contour lines substantially reduced the surface roughness, expressed by the arithmetic mean height, from values as high as 30 µm to 13 µm, while the residual stresses rose from ~340 to about 800 MPa. At this stress level, manufactured rocket fuel injector components evidenced macroscopic cracking. A scan strategy completing the contour region at 100 W and 1050 mm/s is recommended as a compromise between residual stresses (625 MPa) and surface quality (14.2 µm). The LPBF builds were monitored with an in-line twin-photodiode-based melt pool monitoring (MPM) system, which revealed a correlation between the intensity quotient I2/I1, the surface roughness, and the residual stresses. Thus, this MPM system can provide a predictive estimate of the surface quality of the samples and resulting residual stresses in the material generated during LPBF.

20.
Int J Biol Macromol ; 164: 2895-2902, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853624

RESUMO

Chitotriosidase (Chit1) and acidic mammalian chitinase (AMCase) have been attracting research interest due to their involvement in various pathological conditions such as Gaucher's disease and asthma, respectively. Both enzymes are highly expressed in mice, while the level of AMCase mRNA was low in human tissues. In addition, the chitinolytic activity of the recombinant human AMCase was significantly lower than that of the mouse counterpart. Here, we revealed a substantially higher chitinolytic and transglycosylation activity of human Chit1 against artificial and natural chitin substrates as compared to the mouse enzyme. We found that the substitution of leucine (L) by tryptophan (W) at position 218 markedly reduced both activities in human Chit1. Conversely, the L218W substitution in mouse Chit1 increased the activity of the enzyme. These results suggest that Chit1 may compensate for the low of AMCase activity in humans, while in mice, highly active AMCase may supplements low Chit1 activity.

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