Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Genet Med ; 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31273343

RESUMO

PURPOSE: To date, heterozygous or homozygous COL12A1 variants have been reported in 13 patients presenting with a clinical phenotype overlapping with collagen VI-related myopathies and Ehlers-Danlos syndrome (EDS). The small number of reported patients limits thorough investigation of this newly identified syndrome, currently coined as myopathic EDS. METHODS: DNA from 78 genetically unresolved patients fulfilling the clinical criteria for myopathic EDS was sequenced using a next-generation panel of COL12A1, COL6A1, COL6A2, and COL6A3. RESULTS: Among this cohort, we identified four pathogenic heterozygous in-frame exon skipping (∆) defects in COL12A1, clustering to the thrombospondin N-terminal region and the adjacent collagenous domain (Δ52, Δ53, Δ54, and Δ56 respectively), one heterozygous COL12A1 arginine-to-cysteine substitution of unclear significance (p.(Arg1863Cys)), and compound heterozygous pathogenic COL6A1 variants (c.[98-6G>A];[301C>T]) in one proband. Variant-specific intracellular accumulation of collagen XII chains, extracellular overmodification of the long isoform and near-absence of the short isoform of collagen XII, and extracellular decrease of decorin and tenascin-X were observed for the COL12A1 variants. In contrast, the COL6A1 variants abolished collagen VI and V deposition and increased tenascin-X levels. CONCLUSION: Our data further support the significant clinical overlap between myopathic EDS and collagen VI-related myopathies, and emphasize the variant-specific consequences of collagen XII defects.

2.
Int J Mol Sci ; 20(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052252

RESUMO

Ectopic mineralization disorders comprise a broad spectrum of inherited or acquired diseases characterized by aberrant deposition of calcium crystals in multiple organs, such as the skin, eyes, kidneys, and blood vessels. Although the precise mechanisms leading to ectopic calcification are still incompletely known to date, various molecular targets leading to a disturbed balance between pro- and anti-mineralizing pathways have been identified in recent years. Vitamin K and its related compounds, mainly those post-translationally activated by vitamin K-dependent carboxylation, may play an important role in the pathogenesis of ectopic mineralization as has been demonstrated in studies on rare Mendelian diseases, but also on highly prevalent disorders, like vascular calcification. This narrative review compiles and summarizes the current knowledge regarding the role of vitamin K, its metabolism, and associated compounds in the pathophysiology of both monogenic ectopic mineralization disorders, like pseudoxanthoma elasticum or Keutel syndrome, as well as acquired multifactorial diseases, like chronic kidney disease. Clinical and molecular aspects of the various disorders are discussed according to the state-of-the-art, followed by a comprehensive literature review regarding the role of vitamin K in molecular pathophysiology and as a therapeutic target in both human and animal models of ectopic mineralization disorders.


Assuntos
Calcinose/metabolismo , Doenças Genéticas Inatas/metabolismo , Vitamina K/metabolismo , Anormalidades Múltiplas , Animais , Calcinose/genética , Doenças das Cartilagens , Doenças Genéticas Inatas/genética , Deformidades Congênitas da Mão , Humanos , Estenose da Valva Pulmonar , Vitamina K/genética
3.
Ann Clin Transl Neurol ; 6(3): 605-609, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30911583

RESUMO

A 60-year-old man is presented with progressive involuntary muscle movements and neuropsychiatric symptoms who developed a variety of additional complaints over 2 years. Brain imaging revealed bilateral basal ganglia calcifications suggesting primary familial brain calcification. Analysis of the SLC20A2 gene revealed a missense mutation (c.541C>T, p.(Arg181Trp)), in silico predicted to be deleterious and not found in available databases. Segregation analysis confirmed his asymptomatic father to harbor the same mutation, though on brain imaging basal ganglia calcifications were found. This report illustrates the intrafamilial variability of the phenotype and generalized myoclonus as the presenting symptom.

5.
Acta Clin Belg ; : 1-5, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30501482

RESUMO

We describe a boy who presented with neonatal hypotonia, followed by delayed motor development and growth impairment. Further evaluation revealed rickets caused by proximal renal tubular dysfunction. At age 3, the boy exhibited dysmorphic features and bilateral cataract. Genetic analysis of the OCRL gene showed a novel variant in exon 13: c.1250T>A, p.Val417Asp; in silico and segregation analysis confirmed the variant to be pathogenic, compatible with the diagnosis of the oculocerebrorenal syndrome of Lowe. Lowe syndrome is a rare multisystemic disorder; the diagnostic triad requires involvement of the eye, central nervous system and the proximal renal tubule. Typical clinical features are congenital cataract, glaucoma, hypotonia, mental and behavioral problems, benign skin lesions, platelet dysfunction and dental abnormalities. Phenotypic features early in life may be nonspecific, which is illustrated by this case with a late manifestation of cataract. Because an early diagnosis can lead to better counseling and treatment, we suggest urinary testing for proteinuria as a part of the evaluation of children with unexplained hypotonia.

6.
Prenat Diagn ; 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30334587

RESUMO

OBJECTIVE: With the replacement of karyotyping by chromosomal microarray (CMA) in invasive prenatal diagnosis, new challenges have arisen. By building a national database, we standardize the classification and reporting of prenatally detected copy number variants (CNVs) across Belgian genetic centers. This database, which will link genetic and ultrasound findings with postnatal development, forms a unique resource to investigate the pathogenicity of variants of uncertain significance and to refine the phenotypic spectrum of pathogenic and susceptibility CNVs. METHODS: The Belgian MicroArray Prenatal (BEMAPRE) consortium is a collaboration of all genetic centers in Belgium. We collected data from all invasive prenatal procedures performed between May 2013 and July 2016. RESULTS: In this three-year period, 13 266 prenatal CMAs were performed. By national agreement, a limited number of susceptibility CNVs and no variants of uncertain significance were reported. Added values for using CMA versus conventional karyotyping were 1.8% in the general invasive population and 2.7% in cases with an ultrasound anomaly. Of the reported CNVs, 31.5% would have remained undetected with non-invasive prenatal test as the first-tier test. CONCLUSION: The establishment of a national database for prenatal CNV data allows for a uniform reporting policy and the investigation of the prenatal and postnatal genotype-phenotype correlation.

7.
Atherosclerosis ; 277: 369-376, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30270073

RESUMO

BACKGROUND AND AIMS: Familial hypercholesterolaemia (FH) is an autosomal dominant lipoprotein disorder characterized by significant elevation of low-density lipoprotein cholesterol (LDL-C) and markedly increased risk of premature cardiovascular disease (CVD). Because of the very high coronary artery disease risk associated with this condition, the prevalence of FH among patients admitted for CVD outmatches many times the prevalence in the general population. Awareness of this disease is crucial for recognizing FH in the aftermath of a hospitalization of a patient with CVD, and also represents a unique opportunity to identify relatives of the index patient, who are unaware they have FH. This article aims to describe a feasible strategy to facilitate the detection and management of FH among patients hospitalized for CVD. METHODS: A multidisciplinary national panel of lipidologists, cardiologists, endocrinologists and cardio-geneticists developed a three-step diagnostic algorithm, each step including three key aspects of diagnosis, treatment and family care. RESULTS: A sequence of tasks was generated, starting with the process of suspecting FH amongst affected patients admitted for CVD, treating them to LDL-C target, finally culminating in extensive cascade-screening for FH in their family. Conceptually, the pathway is broken down into 3 phases to provide the treating physicians with a time-efficient chain of priorities. CONCLUSIONS: We emphasize the need for optimal collaboration between the various actors, starting with a "vigilant doctor" who actively develops the capability or framework to recognize potential FH patients, continuing with an "FH specialist", and finally involving the patient himself as "FH ambassador" to approach his/her family and facilitate cascade screening and subsequent treatment of relatives.

8.
Nat Genet ; 50(10): 1442-1451, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30224647

RESUMO

The etiological spectrum of ultra-rare developmental disorders remains to be fully defined. Chromatin regulatory mechanisms maintain cellular identity and function, where misregulation may lead to developmental defects. Here, we report pathogenic variations in MSL3, which encodes a member of the chromatin-associated male-specific lethal (MSL) complex responsible for bulk histone H4 lysine 16 acetylation (H4K16ac) in flies and mammals. These variants cause an X-linked syndrome affecting both sexes. Clinical features of the syndrome include global developmental delay, progressive gait disturbance, and recognizable facial dysmorphism. MSL3 mutations affect MSL complex assembly and activity, accompanied by a pronounced loss of H4K16ac levels in vivo. Patient-derived cells display global transcriptome alterations of pathways involved in morphogenesis and cell migration. Finally, we use histone deacetylase inhibitors to rebalance acetylation levels, alleviating some of the molecular and cellular phenotypes of patient cells. Taken together, we characterize a syndrome that allowed us to decipher the developmental importance of MSL3 in humans.

9.
Eur J Hum Genet ; 26(10): 1462-1477, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29955172

RESUMO

Primary familial brain calcification (PFBC) is a rare cerebral microvascular calcifying disorder with a wide spectrum of motor, cognitive, and neuropsychiatric symptoms. It is typically inherited as an autosomal-dominant trait with four causative genes identified so far: SLC20A2, PDGFRB, PDGFB, and XPR1. Our study aimed at screening the coding regions of these genes in a series of 177 unrelated probands that fulfilled the diagnostic criteria for primary brain calcification regardless of their family history. Sequence variants were classified as pathogenic, likely pathogenic, or of uncertain significance (VUS), based on the ACMG-AMP recommendations. We identified 45 probands (25.4%) carrying either pathogenic or likely pathogenic variants (n = 34, 19.2%) or VUS (n = 11, 6.2%). SLC20A2 provided the highest contribution (16.9%), followed by XPR1 and PDGFB (3.4% each), and PDGFRB (1.7%). A total of 81.5% of carriers were symptomatic and the most recurrent symptoms were parkinsonism, cognitive impairment, and psychiatric disturbances (52.3%, 40.9%, and 38.6% of symptomatic individuals, respectively), with a wide range of age at onset (from childhood to 81 years). While the pathogenic and likely pathogenic variants identified in this study can be used for genetic counseling, the VUS will require additional evidence, such as recurrence in unrelated patients, in order to be classified as pathogenic.

10.
Brain Pathol ; 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29722917

RESUMO

Ischemic stroke causes a high mortality and morbidity worldwide. It results from a complex interplay of incompletely known environmental and genetic risk factors. We investigated the ABCC6 gene as a candidate risk factor for ischemic stroke because of the increased ischemic stroke incidence in the autosomal recessive disorder pseudoxanthoma elasticum, caused by biallelic pathogenic ABCC6 variants, the higher cardiovascular risk in heterozygous carriers and the established role of ABCC6 dysfunction in myocardial ischemia. We established segregation of a known pathogenic ABCC6 variant (p.(Arg1314Gln)) in 11/19 family members of an ischemic stroke patient in a large multigenerational family suffering from ischemic stroke and/or cardiovascular disease at a relatively young age. In an independent case-control study in 424 ischemic stroke patients and 250 healthy controls, pathogenic ABCC6 variants were 4.9 times more frequent (p = 0.036; 95% confidence interval 1.11-21.33) in the ischemic stroke patient cohort. To study cellular consequences of ABCC6 deficiency in the brain, immunostaining of brain sections in Abcc6-deficient mice and wildtype controls were performed. An upregulation of Bmp4 and Eng and a downregulation of Alk2 was identified in Abcc6-/- mice, suggesting an increase in apoptosis and angiogenesis. As both of these processes are induced in ischemia, we propose that a pro-ischemic state may explain the higher risk to suffer from ischemic stroke in patients carrying a pathogenic ABCC6 variant, as this may lower the threshold to develop acute ischemic events in these patients. In conclusion, this study identified heterozygous ABCC6 variants as a risk factor for ischemic stroke. Further, dysregulation of Bmp (Bmp4, Alk2) and Tgfß (Eng) signaling in the brain of Abcc6-/- mice could lead to a pro-ischemic state, lowering the threshold to develop acute ischemic events. These data demonstrate the importance of a molecular analysis of the ABCC6 gene in patients diagnosed with cryptogenic ischemic stroke. This article is protected by copyright. All rights reserved.

11.
Am J Med Genet B Neuropsychiatr Genet ; 177(4): 397-405, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29603867

RESUMO

Recurrent deletions and duplications at the 2q13 locus have been associated with developmental delay (DD) and dysmorphisms. We aimed to undertake detailed clinical characterization of individuals with 2q13 copy number variations (CNVs), with a focus on behavioral and psychiatric phenotypes. Participants were recruited via the Unique chromosomal disorder support group, U.K. National Health Service Regional Genetics Centres, and the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources (DECIPHER) database. A review of published 2q13 patient case reports was undertaken to enable combined phenotypic analysis. We present a new case series of 2q13 CNV carriers (21 deletion, 4 duplication) and the largest ever combined analysis with data from published studies, making a total of 54 deletion and 23 duplication carriers. DD/intellectual disabilities was identified in the majority of carriers (79% deletion, 70% duplication), although in the new cases 52% had an IQ in the borderline or normal range. Despite the median age of the new cases being only 9 years, 64% had a clinical psychiatric diagnosis. Combined analysis found attention deficit hyperactivity disorder (ADHD) to be the most frequent diagnosis (48% deletion, 60% duplication), followed by autism spectrum disorders (33% deletion, 17% duplication). Aggressive (33%) and self-injurious behaviors (33%) were also identified in the new cases. CNVs at 2q13 are typically associated with DD with mildly impaired intelligence, and a high rate of childhood psychiatric diagnoses-particularly ADHD. We have further characterized the clinical phenotype related to imbalances of the 2q13 region and identified it as a region of interest for the neurobiological investigation of ADHD.

12.
JAMA Neurol ; 75(5): 557-565, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29435569

RESUMO

Importance: Mutations in the titin gene (TTN) cause a wide spectrum of genetic diseases. The interpretation of the numerous rare variants identified in TTN is a difficult challenge given its large size. Objective: To identify genetic variants in titin in a cohort of patients with muscle disorders. Design, Setting, and Participants: In this case series, 9 patients with titinopathy and 4 other patients with possibly disease-causing variants in TTN were identified. Titin mutations were detected through targeted resequencing performed on DNA from 504 patients with muscular dystrophy, congenital myopathy, or other skeletal muscle disorders. Patients were enrolled from 10 clinical centers in April 2012 to December 2013. All of them had not received a diagnosis after undergoing an extensive investigation, including Sanger sequencing of candidate genes. The data analysis was performed between September 2013 and January 2017. Sequencing data were analyzed using an internal custom bioinformatics pipeline. Main Outcomes and Measures: The identification of novel mutations in the TTN gene and novel patients with titinopathy. We performed an evaluation of putative causative variants in the TTN gene, combining genetic, clinical, and imaging data with messenger RNA and/or protein studies. Results: Of the 9 novel patients with titinopathy, 5 (55.5%) were men and the mean (SD) age at onset was 25 (15.8) years (range, 0-46 years). Of the 4 other patients (3 men and 1 woman) with possibly disease-causing TTN variants, 2 (50%) had a congenital myopathy and 2 (50%) had a slowly progressive distal myopathy with onset in the second decade. Most of the identified mutations were previously unreported. However, all the variants, even the already described mutations, require careful clinical and molecular evaluation of probands and relatives. Heterozygous truncating variants or unique missense changes are not sufficient to make a diagnosis of titinopathy. Conclusions and Relevance: The interpretation of TTN variants often requires further analyses, including a comprehensive evaluation of the clinical phenotype (deep phenotyping) as well as messenger RNA and protein studies. We propose a specific workflow for the clinical interpretation of genetic findings in titin.

13.
J Med Genet ; 54(9): 613-623, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28735298

RESUMO

BACKGROUND: Mutations in forkhead box protein P1 (FOXP1) cause intellectual disability (ID) and specific language impairment (SLI), with or without autistic features (MIM: 613670). Despite multiple case reports no specific phenotype emerged so far. METHODS: We correlate clinical and molecular data of 25 novel and 23 previously reported patients with FOXP1 defects. We evaluated FOXP1 activity by an in vitro luciferase model and assessed protein stability in vitro by western blotting. RESULTS: Patients show ID, SLI, neuromotor delay (NMD) and recurrent facial features including a high broad forehead, bent downslanting palpebral fissures, ptosis and/or blepharophimosis and a bulbous nasal tip. Behavioural problems and autistic features are common. Brain, cardiac and urogenital malformations can be associated. More severe ID and NMD, sensorineural hearing loss and feeding difficulties are more common in patients with interstitial 3p deletions (14 patients) versus patients with monogenic FOXP1 defects (34 patients). Mutations result in impaired transcriptional repression and/or reduced protein stability. CONCLUSIONS: FOXP1-related ID syndrome is a recognisable entity with a wide clinical spectrum and frequent systemic involvement. Our data will be helpful to evaluate genotype-phenotype correlations when interpreting next-generation sequencing data obtained in patients with ID and/or SLI and will guide clinical management.


Assuntos
Fatores de Transcrição Forkhead/genética , Deficiência Intelectual/genética , Proteínas Repressoras/genética , Transtorno do Espectro Autista/genética , Face/anormalidades , Feminino , Fatores de Transcrição Forkhead/química , Fatores de Transcrição Forkhead/metabolismo , Humanos , Transtornos da Linguagem/genética , Masculino , Transtornos das Habilidades Motoras/genética , Mutação , Mutação de Sentido Incorreto , Transtornos do Neurodesenvolvimento/genética , Fenótipo , Estabilidade Proteica , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Síndrome , Transcrição Genética
14.
Int J Mol Sci ; 18(2)2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28125048

RESUMO

Gamma-carboxylation, performed by gamma-glutamyl carboxylase (GGCX), is an enzymatic process essential for activating vitamin K-dependent proteins (VKDP) with important functions in various biological processes. Mutations in the encoding GGCX gene are associated with multiple phenotypes, amongst which vitamin K-dependent coagulation factor deficiency (VKCFD1) is best known. Other patients have skin, eye, heart or bone manifestations. As genotype-phenotype correlations were never described, literature was systematically reviewed in search of patients with at least one GGCX mutation with a phenotypic description, resulting in a case series of 47 patients. Though this number was too low for statistically valid correlations-a frequent problem in orphan diseases-we demonstrate the crucial role of the horizontally transferred transmembrane domain in developing cardiac and bone manifestations. Moreover, natural history suggests ageing as the principal determinant to develop skin and eye symptoms. VKCFD1 symptoms seemed more severe in patients with both mutations in the same protein domain, though this could not be linked to a more perturbed coagulation factor function. Finally, distinct GGCX functional domains might be dedicated to carboxylation of very specific VKDP. In conclusion, this systematic review suggests that there indeed may be genotype-phenotype correlations for GGCX-related phenotypes, which can guide patient counseling and management.


Assuntos
Carbono-Carbono Ligases/genética , Carbono-Carbono Ligases/metabolismo , Estudos de Associação Genética , Genótipo , Fenótipo , Transtornos Herdados da Coagulação Sanguínea/diagnóstico , Transtornos Herdados da Coagulação Sanguínea/genética , Carbono-Carbono Ligases/química , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/genética , Olho/patologia , Técnicas de Inativação de Genes , Aconselhamento Genético , Predisposição Genética para Doença , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Domínios e Motivos de Interação entre Proteínas , Pele/metabolismo , Pele/patologia , Vitamina K/metabolismo
16.
Eur J Med Genet ; 59(10): 502-6, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27633570

RESUMO

There are no published reports of patients harboring microdeletions involving the 7p22.1 region. Although 7p22.1 microdeletions are rare, some reports have shown microduplications encompassing this region. In this study, we report five patients with overlapping deletions of the 7p22.1 region. The patients exhibited clinical similarities including non-specific developmental delay, short stature, microcephaly, and other distinctive features. The shortest region of overlap within the 7p22.1 region includes five genes, FBXL18, ACTB, FSCN1, RNF216, and ZNF815P. Of these genes, only ACTB is known to be associated with an autosomal dominant trait. Dominant negative mutations in ACTB are responsible for Baraitser-Winter syndrome 1. We analyzed ACTB expression in immortalized lymphocytes derived from one of the patients and found that it was reduced to approximately half that observed in controls. This indicates that ACTB expression is linearly correlated with the gene copy number. We suggest that haploinsufficiency of ACTB may be responsible for the clinical features of patients with 7p22.1 microdeletions.


Assuntos
Actinas/genética , Deficiências do Desenvolvimento/genética , Nanismo/genética , Microcefalia/genética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/fisiopatologia , Actinas/biossíntese , Adolescente , Adulto , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Deficiências do Desenvolvimento/fisiopatologia , Nanismo/fisiopatologia , Feminino , Expressão Gênica/genética , Haploinsuficiência/genética , Humanos , Lactente , Recém-Nascido , Linfócitos/metabolismo , Linfócitos/patologia , Masculino , Microcefalia/fisiopatologia , Fenótipo
17.
Am J Hum Genet ; 99(1): 125-38, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27374770

RESUMO

DNA replication precisely duplicates the genome to ensure stable inheritance of genetic information. Impaired licensing of origins of replication during the G1 phase of the cell cycle has been implicated in Meier-Gorlin syndrome (MGS), a disorder defined by the triad of short stature, microtia, and a/hypoplastic patellae. Biallelic partial loss-of-function mutations in multiple components of the pre-replication complex (preRC; ORC1, ORC4, ORC6, CDT1, or CDC6) as well as de novo stabilizing mutations in the licensing inhibitor, GMNN, cause MGS. Here we report the identification of mutations in CDC45 in 15 affected individuals from 12 families with MGS and/or craniosynostosis. CDC45 encodes a component of both the pre-initiation (preIC) and CMG helicase complexes, required for initiation of DNA replication origin firing and ongoing DNA synthesis during S-phase itself, respectively, and hence is functionally distinct from previously identified MGS-associated genes. The phenotypes of affected individuals range from syndromic coronal craniosynostosis to severe growth restriction, fulfilling diagnostic criteria for Meier-Gorlin syndrome. All mutations identified were biallelic and included synonymous mutations altering splicing of physiological CDC45 transcripts, as well as amino acid substitutions expected to result in partial loss of function. Functionally, mutations reduce levels of full-length transcripts and protein in subject cells, consistent with partial loss of CDC45 function and a predicted limited rate of DNA replication and cell proliferation. Our findings therefore implicate the preIC as an additional protein complex involved in the etiology of MGS and connect the core cellular machinery of genome replication with growth, chondrogenesis, and cranial suture homeostasis.


Assuntos
Proteínas de Ciclo Celular/genética , Microtia Congênita/genética , Craniossinostoses/genética , Transtornos do Crescimento/genética , Micrognatismo/genética , Mutação , Patela/anormalidades , Adolescente , Adulto , Alelos , Processamento Alternativo/genética , Sequência de Aminoácidos , Âmnio/citologia , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Células Cultivadas , Criança , Pré-Escolar , Análise Mutacional de DNA , Replicação do DNA , Exoma/genética , Éxons/genética , Feminino , Estudos de Associação Genética , Humanos , Masculino , Modelos Moleculares , Conformação Proteica , Síndrome , Adulto Jovem
18.
Ann Otol Rhinol Laryngol ; 125(9): 734-45, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27242366

RESUMO

BACKGROUND: The 6p25 deletion syndrome is one of the many syndromes with both hearing impairment as well as vision impairment. However, the audiometric characteristics and radiological findings of patients with 6p25 deletions are only scarcely described in literature. This study focused on characterizing the audiometric and radiological features of a Belgian family with a chromosome 6p25 deletion. OBJECTIVE: To evaluate the hearing impairment, audiometric testing and radiological examination of the temporal bones in 3 family members with a 3.4 Mb deletion in chromosome band 6p25. RESULTS: All 3 family members demonstrated slowly progressive sensorineural or mixed hearing impairment. Radiologic examination revealed thickened and sclerotic stapes in all patients and a minor internal partition type II of the cochlea in 2 patients. CONCLUSION: There is a significant phenotypic variability within and among families with the 6p25 deletion syndrome. A thorough genotype-phenotype correlation is difficult because of the small number of affected patients and the limited clinical data available. More clinical data of families with 6p25 deletions need to be published in order to create a reliable and precise phenotypic characterization. However, our findings can facilitate counseling of hearing impairment caused by 6p25 deletions.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 6 , Perda Auditiva Condutiva-Neurossensorial Mista/genética , Perda Auditiva Neurossensorial/genética , Adulto , Segmento Anterior do Olho/anormalidades , Bélgica , Doenças Cocleares/diagnóstico por imagem , Deficiências do Desenvolvimento/genética , Progressão da Doença , Feminino , Fatores de Transcrição Forkhead/genética , Glaucoma/genética , Humanos , Masculino , Miringoesclerose/diagnóstico por imagem , Miringoesclerose/genética , Fenótipo , Esclerose/diagnóstico por imagem , Estribo/diagnóstico por imagem , Estribo/patologia , Substância Branca/anormalidades , Substância Branca/diagnóstico por imagem
19.
Biomed Res Int ; 2015: 648569, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26356190

RESUMO

The knowledge on the genetic etiology of complex disorders largely results from the study of rare monogenic disorders. Often these common and rare diseases show phenotypic overlap, though monogenic diseases generally have a more extreme symptomatology. ABCC6, the gene responsible for pseudoxanthoma elasticum, an autosomal recessive ectopic mineralization disorder, can be considered a paradigm gene with relevance that reaches far beyond this enigmatic orphan disease. Indeed, common traits such as chronic kidney disease or cardiovascular disorders have been linked to the ABCC6 gene. While during the last decade the awareness of the wide ramifications of ABCC6 has increased significantly, the gene itself and the transmembrane transporter it encodes have not unveiled all of the mysteries that surround them. To gain more insights, multiple approaches are being used including next-generation sequencing, computational methods, and various "omics" technologies. Much effort is made to place the vast amount of data that is gathered in an integrated system-biological network; the involvement of ABCC6 in common disorders provides a good view on the wide implications and potential of such a network. In this review, we summarize the network approaches used to study ABCC6 and the role of this gene in several complex diseases.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Doenças Raras/genética , Animais , Transporte Biológico/genética , Humanos , Proteínas de Membrana Transportadoras/genética , Pseudoxantoma Elástico/genética
20.
World J Clin Cases ; 3(7): 556-74, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26244149

RESUMO

Ectopic mineralization - inappropriate biomineralization in soft tissues - is a frequent finding in physiological aging processes and several common disorders, which can be associated with significant morbidity and mortality. Further, pathologic mineralization is seen in several rare genetic disorders, which often present life-threatening phenotypes. These disorders are classified based on the mechanisms through which the mineralization occurs: metastatic or dystrophic calcification or ectopic ossification. Underlying mechanisms have been extensively studied, which resulted in several hypotheses regarding the etiology of mineralization in the extracellular matrix of soft tissue. These hypotheses include intracellular and extracellular mechanisms, such as the formation of matrix vesicles, aberrant osteogenic and chondrogenic signaling, apoptosis and oxidative stress. Though coherence between the different findings is not always clear, current insights have led to improvement of the diagnosis and management of ectopic mineralization patients, thus translating pathogenetic knowledge (variome) to the phenotype (phenome). In this review, we will focus on the clinical presentation, pathogenesis and management of primary genetic soft tissue mineralization disorders. As examples of dystrophic calcification disorders Pseudoxanthoma elasticum, Generalized arterial calcification of infancy, Keutel syndrome, Idiopathic basal ganglia calcification and Arterial calcification due to CD73 (NT5E) deficiency will be discussed. Hyperphosphatemic familial tumoral calcinosis will be reviewed as an example of mineralization disorders caused by metastatic calcification.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA