Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Genet Med ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31363182

RESUMO

PURPOSE: Kabuki syndrome (KS) (OMIM 147920 and 300867) is a rare genetic disorder characterized by specific facial features, intellectual disability, and various malformations. Immunopathological manifestations seem prevalent and increase the morbimortality. To assess the frequency and severity of the manifestations, we measured the prevalence of immunopathological manifestations as well as genotype-phenotype correlations in KS individuals from a registry. METHODS: Data were for 177 KS individuals with KDM6A or KMT2D pathogenic variants. Questionnaires to clinicians were used to assess the presence of immunodeficiency and autoimmune diseases both on a clinical and biological basis. RESULTS: Overall, 44.1% (78/177) and 58.2% (46/79) of KS individuals exhibited infection susceptibility and hypogammaglobulinemia, respectively; 13.6% (24/177) had autoimmune disease (AID; 25.6% [11/43] in adults), 5.6% (10/177) with ≥2 AID manifestations. The most frequent AID manifestations were immune thrombocytopenic purpura (7.3% [13/177]) and autoimmune hemolytic anemia (4.0% [7/177]). Among nonhematological manifestations, vitiligo was frequent. Immune thrombocytopenic purpura was frequent with missense versus other types of variants (p = 0.027). CONCLUSION: The high prevalence of immunopathological manifestations in KS demonstrates the importance of systematic screening and efficient preventive management of these treatable and sometimes life-threatening conditions.

2.
Am J Med Genet C Semin Med Genet ; 181(3): 337-344, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31368648

RESUMO

Arthrogryposis multiplex congenita, or AMC, is a clinical sign defined as congenital contractures of at least two joint levels. These joint contractures are always secondary to diminished fetal movement which can have numerous causes that affect any part of the anatomical structures implicated in movement: the central nervous system, the anterior horn cell, the nerve, the neuromuscular junction, the muscle, or the joint itself. Make a precise diagnosis of the cause in a patient with multiple joint contractures is therefore challenging. The aim of this article is to summarize the use and diagnostic value of common examinations and analyses performed postnatally in patients affected by AMC from a literature review. We also compare this data with results from our clinical practice. Even though it is difficult to give precise guidelines today, it appears that genetic studies, such as whole exome or genome analysis in all patients and chromosomal microarray analysis in patients with intellectual disability and AMC should be preferred as first tier investigations over EMG and muscle biopsy.

3.
Am J Med Genet C Semin Med Genet ; 181(3): 345-353, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31410997

RESUMO

Arthrogryposis or AMC, arthrogryposis multiplex congenita, is defined as multiple congenital joint contractures in more than two joints and in different body areas. The common cause of all AMC is lack of movement in utero, which in turn can have different causes, one of which is CNS involvement. Intellectual disability/CNS involvement is found in approximately 25% of all AMC. AMC with CNS involvement includes a large number of genetic syndromes. So far, more than 400 genes have been identified as linked to AMC, with and without CNS involvement. A number of neonatally lethal syndromes and syndromes resulting in severe disability due to CNS malfunction belong to this group of syndromes. There are several X-linked disorders with AMC, which are primarily related to intellectual disability. A number of neuromuscular disorders may include AMC and CNS/brain involvement. Careful clinical evaluation by a geneticist and a pediatrician/pediatric neurologist is the first step in making a specific diagnosis. Further investigations may include MRI of the brain and spinal cord, electroencephalogram, blood chemistry for muscle enzymes, other organ investigations (ophtalmology, cardiology, gastrointestinal, and genitourinary systems). Nerve conduction studies, electromyogram, and muscle pathology may be of help when there is associated peripheral nervous system involvement. But most importantly, genetic investigations with targeted or rather whole exome or genome sequencing should be performed. A correct diagnosis is important in planning adequate treatment, in genetic counselling and also for future understanding of pathogenic mechanisms and possible new treatments. A multidiciplinary team is needed both in investigation and treatment.

4.
Genet Med ; 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31267042

RESUMO

In the Acknowledgements section of the paper the authors neglected to mention that the study was supported by a grant from the National Human Genome Research Institute (NHGRI) UM1HG007301 (S.H., M.L.T.). In addition, the award of MD was associated with the authors Michelle L. Thompson and Susan Hiatt instead of PhD. The PDF and HTML versions of the Article have been modified accordingly.

6.
Am J Med Genet C Semin Med Genet ; 181(3): 300-303, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271512

RESUMO

There is a need for a system to classify various forms of arthrogryposis. None is satisfactory or complete. Nevertheless, several have been developed to meet the needs of clinicians, prenatal diagnosticians, researchers, and basic scientists. They all await more insight into basic mechanisms.

7.
Am J Med Genet C Semin Med Genet ; 181(3): 288-299, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31282072

RESUMO

Arthrogryposis multiplex congenita (AMC) has been described and defined in thousands of articles, but the terminology used has been inconsistent in clinical and research communities. A definition of AMC was recently developed using a modified Delphi consensus method involving 25 experts in the field of AMC from 8 countries. Participants included health care professionals, researchers, and individuals with AMC. An annotation of the definition provides more in-depth explanations of the different sentences of the AMC definition and is useful to complement the proposed definition. The aim of this study was to provide an annotation of the proposed consensus-based AMC definition. For the annotation process, 17 experts in AMC representing 10 disciplines across 7 countries participated. A paragraph was developed for each sentence of the definition using an iterative process involving multiple authors with varied and complementary expertise, ensuring all points of view were taken into consideration. The annotated definition provides an overview of the different topics related to AMC and is intended for all stakeholders, including youth and adults with AMC, their families, and clinicians and researchers, with the hopes of unifying the understanding of AMC in the international community.

8.
Genet Med ; 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31155615

RESUMO

PURPOSE: Mediator is a multiprotein complex that allows the transfer of genetic information from DNA binding proteins to the RNA polymerase II during transcription initiation. MED12L is a subunit of the kinase module, which is one of the four subcomplexes of the mediator complex. Other subunits of the kinase module have been already implicated in intellectual disability, namely MED12, MED13L, MED13, and CDK19. METHODS: We describe an international cohort of seven affected individuals harboring variants involving MED12L identified by array CGH, exome or genome sequencing. RESULTS: All affected individuals presented with intellectual disability and/or developmental delay, including speech impairment. Other features included autism spectrum disorder, aggressive behavior, corpus callosum abnormality, and mild facial morphological features. Three individuals had a MED12L deletion or duplication. The other four individuals harbored single-nucleotide variants (one nonsense, one frameshift, and two splicing variants). Functional analysis confirmed a moderate and significant alteration of RNA synthesis in two individuals. CONCLUSION: Overall data suggest that MED12L haploinsufficiency is responsible for intellectual disability and transcriptional defect. Our findings confirm that the integrity of this kinase module is a critical factor for neurological development.

9.
Eur J Hum Genet ; 27(9): 1406-1418, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30996334

RESUMO

Currently only 25-30% of patients with axonal forms of Charcot-Marie-Tooth disease (CMT) receive a genetic diagnosis. We aimed to identify the causative gene of CMT type 2 in 8 non-related French families with a distinct clinical phenotype. We collected clinical, electrophysiological, and laboratory findings and performed genetic analyses in four different French laboratories. Seventy-two patients with autosomal dominant inheritance were identified. The disease usually started in the fourth decade and the clinical picture was dominated by sensory ataxia (80%), neuropathic pain (38%), and length-dependent sensory loss to all modalities. Electrophysiological studies showed a primarily axonal neuropathy, with possible isolated sensory involvement in milder phenotypes. Disease severity varied greatly but the clinical course was generally mild. We identified 2 novel variants in LRSAM1 gene: a deletion of 4 amino acids, p.(Gln698_Gln701del), was found in 7 families and a duplication of a neighboring region of 10 amino acids, p.(Pro702_Gln711dup), in the remaining family. A common haplotype of ~450 kb suggesting a founder effect was noted around LRSAM1 in 4 families carrying the first variant. LRSAM1 gene encodes for an E3 ubiquitin ligase important for neural functioning. Our results confirm the localization of variants in its catalytic C-terminal RING domain and broaden the phenotypic spectrum of LRSAM1-related neuropathies, including painful and predominantly sensory ataxic forms.

10.
Am J Med Genet A ; 179(6): 915-926, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30868735

RESUMO

Mutations in the CHRNG gene cause autosomal recessive multiple pterygium syndrome (MPS). Herein we present a long-term follow-up of seven patients with CHRNG-related nonlethal MPS and we compare them with the 57 previously published patients. The objective is defining not only the clinical, histopathological, and molecular genetic characteristics, but also the type and degree of muscle involvement on whole-body magnetic resonance imaging (WBMRI). CHRNG mutations lead to a distinctive phenotype characterized by multiple congenital contractures, pterygium, and facial dysmorphism, with a stable clinical course over the years. Postnatal abnormalities at the neuromuscular junction were observed in the muscle biopsy of these patients. WBMRI showed distinctive features different from other arthrogryposis multiple congenita. A marked muscle bulk reduction is the predominant finding, mostly affecting the spinal erector muscles and gluteus maximus. Fatty infiltration was only observed in deep paravertebral muscles and distal lower limbs. Mutations in CHRNG are mainly located at the extracellular domain of the protein. Our study contributes to further define the phenotypic spectrum of CHRNG-related nonlethal MPS, including muscle imaging features, which may be useful in distinguishing it from other diffuse arthrogryposis entities.

12.
Am J Med Genet A ; 179(4): 650-654, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30737907

RESUMO

The AMME syndrome defined as the combination of Alport syndrome, intellectual disability, midface hypoplasia, and elliptocytosis (AMME) is known to be a contiguous gene syndrome associated with microdeletions in the region Xq22.3q23. Recently, using exome sequencing, missense pathogenic variants in AMMECR1 have been associated with intellectual disability, midface hypoplasia, and elliptocytosis. In these cases, AMMECR1 gene appears to be responsible for most of the clinical features of the AMME syndrome except for Alport syndrome. In this article, we present two unrelated male patients with short stature, mild intellectual disability or neurodevelopmental delay, sensorineural hearing loss, and elliptocytosis harboring small microdeletions identified by array-CGH involving TMEM164 and AMMECR1 genes and SNORD96B small nucleolar RNA for one patient, inherited from their mothers. These original cases further confirm that most specific AMME features are ascribed to AMMECR1 haploinsufficiency. These cases reporting the smallest microdeletions encompassing AMMECR1 gene provide new evidence for involvement of AMMECR1 in the AMME phenotype and permit to discuss a phenotype related to AMMECR1 haploinsufficiency: developmental delay/intellectual deficiency, midface hypoplasia, midline defect, deafness, and short stature.

13.
Neuromuscul Disord ; 29(2): 114-126, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30598237

RESUMO

Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder characterized by progressive motor and respiratory decline during the first year of life. Early and late-onset cases have recently been reported, although not meeting the established diagnostic criteria, these cases have been genotyped. We thus conducted a national multicenter observational retrospective study to determine the prognosis of children with SMARD1 according to their phenotype. We recorded all known French pediatric cases with mutations identified on the immunoglobulin µ-binding protein 2 gene and the presence of respiratory symptoms. Thirty centers provided 22 observations. A diaphragmatic palsy was diagnosed 1.5 months (p = 0.02) after first respiratory symptoms, and hypotonia preceded areflexia by 4 months (p = 0.02). Early onset of symptoms leading to specialist consultation before the age of 3 months was associated with a significantly worse prognosis (p < 0.01). Among the 6 patients who were still alive, all were tracheostomized. Only one case survived beyond 2 years without artificial ventilation. The remaining patients died at a median age of 7 months. Our results may help pediatricians to provide medical information to parents and improve the decision-making process of setting up life support.

14.
J Med Genet ; 55(6): 359-371, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29618507

RESUMO

The Xq28 duplication involving the MECP2 gene (MECP2 duplication) has been mainly described in male patients with severe developmental delay (DD) associated with spasticity, stereotypic movements and recurrent infections. Nevertheless, only a few series have been published. We aimed to better describe the phenotype of this condition, with a focus on morphological and neurological features. Through a national collaborative study, we report a large French series of 59 affected males with interstitial MECP2 duplication. Most of the patients (93%) shared similar facial features, which evolved with age (midface hypoplasia, narrow and prominent nasal bridge, thick lower lip, large prominent ears), thick hair, livedo of the limbs, tapered fingers, small feet and vasomotor troubles. Early hypotonia and global DD were constant, with 21% of patients unable to walk. In patients able to stand, lower limbs weakness and spasticity led to a singular standing habitus: flexion of the knees, broad-based stance with pseudo-ataxic gait. Scoliosis was frequent (53%), such as divergent strabismus (76%) and hypermetropia (54%), stereotypic movements (89%), without obvious social withdrawal and decreased pain sensitivity (78%). Most of the patients did not develop expressive language, 35% saying few words. Epilepsy was frequent (59%), with a mean onset around 7.4 years of age, and often (62%) drug-resistant. Other medical issues were frequent: constipation (78%), and recurrent infections (89%), mainly lung. We delineate the clinical phenotype of MECP2 duplication syndrome in a large series of 59 males. Pulmonary hypertension appeared as a cause of early death in these patients, advocating its screening early in life.

15.
Neurology ; 90(18): e1596-e1604, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29626181

RESUMO

OBJECTIVE: To understand the disability of adults with arthrogryposis multiplex congenita (AMC), a rare disease spectrum characterized by at least 2 joint contractures at birth in different body areas. METHODS: This is a retrospective analysis of data for unselected persons with AMC referred to the French center for adults with AMC from 2010 to 2016. All underwent a pluriprofessional systematic and comprehensive investigation of deficits, activity limitation, and participation restriction according to the International Classification of Functioning, Disability and Health and genetic analysis when indicated. Participants were divided by amyoplasia and other AMC types. RESULTS: Mean (SD) age of the 43 participants (27 female) was 33.2 (13.4) years; 28 had amyoplasia and 15 other types of AMC. Beyond joint stiffness, deformities, and muscle weakness, the well-known core symptoms that we quantified and for which first-line treatment involved technical aids, other less visible disorders that could contribute to severe participation restriction were particularly pain and psychological problems including anxiety, fatigue, difficulty in sexual life, altered self-esteem, and feelings of solitude. Severe respiratory disorders were infrequent and were linked to PIEZO2 mutations. Gait disorders were not due to respiratory impairment but to skeletal problems and were always associated with amyoplasia when severe. Functional independence was worse but respiratory and swallowing capacities were better with amyoplasia than other AMC types. CONCLUSION: This study describes disability patterns of a cohort of adults with AMC by genotype. The disability of adults with AMC is influenced by genotype, with important invisible disability.

16.
Am J Med Genet A ; 176(2): 460-464, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29226564

RESUMO

Lowe syndrome (LS) is a very rare disorder of phosphatidylinositol metabolism, which manifests with a complex phenotype comprising a clinical triad encompassing major abnormalities of the eyes, the kidneys, and the central nervous system. We are reporting a 23-year-old Egyptian male with a severe phenotype of LS with a minimal kidney disease. Direct sequencing of the OCRL gene detected a p.His375Arg mutation in the catalytic domain of the protein. The patient suffered from bilateral congenital cataracts and glaucoma, striking growth deficiency, severe psychomotor disability, a severe osteopathy, and seizures, but only minimal renal dysfunction. Although the biological mechanisms underlying the pathophysiology of LS manifestations is yet unclear, it has been proposed that growth delay and osteopathy are linked to a renal dysfunction. This report, however, argues this association and suggests that kidney dysfunction may partially explain the growth deficiency and bone abnormalities, but other still undefined factors might have a potential impact.

17.
NPJ Genom Med ; 2: 32, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263841

RESUMO

Phelan-McDermid syndrome (PMS) is characterized by a variety of clinical symptoms with heterogeneous degrees of severity, including intellectual disability (ID), absent or delayed speech, and autism spectrum disorders (ASD). It results from a deletion of the distal part of chromosome 22q13 that in most cases includes the SHANK3 gene. SHANK3 is considered a major gene for PMS, but the factors that modulate the severity of the syndrome remain largely unknown. In this study, we investigated 85 patients with different 22q13 rearrangements (78 deletions and 7 duplications). We first explored the clinical features associated with PMS, and provide evidence for frequent corpus callosum abnormalities in 28% of 35 patients with brain imaging data. We then mapped several candidate genomic regions at the 22q13 region associated with high risk of clinical features, and suggest a second locus at 22q13 associated with absence of speech. Finally, in some cases, we identified additional clinically relevant copy-number variants (CNVs) at loci associated with ASD, such as 16p11.2 and 15q11q13, which could modulate the severity of the syndrome. We also report an inherited SHANK3 deletion transmitted to five affected daughters by a mother without ID nor ASD, suggesting that some individuals could compensate for such mutations. In summary, we shed light on the genotype-phenotype relationship of patients with PMS, a step towards the identification of compensatory mechanisms for a better prognosis and possibly treatments of patients with neurodevelopmental disorders.

18.
Hum Mol Genet ; 26(20): 3989-3994, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29016857

RESUMO

Arthrogryposis multiplex congenita (AMC) is a developmental condition characterized by multiple joint contractures resulting from reduced or absent fetal movements. Homozygosity mapping of disease loci combined with whole exome sequencing in a consanguineous family presenting with lethal AMC allowed the identification of a homozygous frameshift deletion in UNC50 gene (c.750_751del:p.Cys251Phefs*4) in the index case. To assess the effect of the mutation, an equivalent mutation in the Caenorhabditis elegans orthologous gene was created using CRISPR/Cas9. We demonstrated that unc-50(kr331) modification caused the loss of acetylcholine receptor (AChR) expression in C. elegans muscle. unc-50(kr331) animals were as resistant to the cholinergic agonist levamisole as unc-50 null mutants suggesting that AChRs were no longer expressed in this animal model. This was confirmed by using a knock-in strain in which a red fluorescent protein was inserted into the AChR locus: no signal was detected in unc-50(kr331) background, suggesting that UNC-50, a protein known to be involved in AChR trafficking, was no longer functional. These data indicate that biallelic mutation in the UNC50 gene underlies AMC through a probable loss of AChR expression at the neuromuscular junction which is essential for the cholinergic transmission during human muscle development.


Assuntos
Artrogripose/genética , Artrogripose/metabolismo , Mutação da Fase de Leitura , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores Colinérgicos/metabolismo , Alelos , Sequência de Aminoácidos , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Junção Neuromuscular/genética , Junção Neuromuscular/metabolismo , Linhagem , Transporte Proteico , Receptores Colinérgicos/genética , Natimorto/genética
19.
J Med Genet ; 54(7): 502-510, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28270404

RESUMO

BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) represent a significant healthcare burden since it is the primary cause of chronic kidney in children. CNVs represent a recurrent molecular cause of CAKUT but the culprit gene remains often elusive. Our study aimed to define the gene responsible for CAKUT in patients with an 1q23.3q24.1 microdeletion. METHODS: We describe eight patients presenting with CAKUT carrying an 1q23.3q24.1 microdeletion as identified by chromosomal microarray analysis (CMA). Clinical features were collected, especially the renal and urinary tract phenotype, and extrarenal features. We characterised PBX1 expression and localisation in fetal and adult kidneys using quantitative RT-PCR and immunohistochemistry. RESULTS: We defined a 276-kb minimal common region (MCR) that only overlaps with the PBX1 gene. All eight patients presented with syndromic CAKUT. CAKUT were mostly bilateral renal hypoplasia (75%). The most frequent extrarenal symptoms were developmental delay and ear malformations. We demonstrate that PBX1 is strongly expressed in fetal kidneys and brain and expression levels decreased in adult samples. In control fetal kidneys, PBX1 was localised in nuclei of medullary, interstitial and mesenchymal cells, whereas it was present in endothelial cells in adult kidneys. CONCLUSIONS: Our results indicate that PBX1 haploinsufficiency leads to syndromic CAKUT as supported by the Pbx1-null mice model. Correct PBX1 dosage appears to be critical for normal nephrogenesis and seems important for brain development in humans. CMA should be recommended in cases of fetal renal anomalies to improve genetic counselling and pregnancy management.


Assuntos
Haploinsuficiência/genética , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Anormalidades Urogenitais/genética , Refluxo Vesicoureteral/genética , Criança , Pré-Escolar , Feminino , Feto/metabolismo , Genoma Humano , Humanos , Lactente , Rim/anormalidades , Rim/embriologia , Rim/metabolismo , Rim/patologia , Masculino , Síndrome
20.
Am J Hum Genet ; 100(1): 105-116, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27939639

RESUMO

Intellectual disability (ID) is a common neurodevelopmental disorder exhibiting extreme genetic heterogeneity, and more than 500 genes have been implicated in Mendelian forms of ID. We performed exome sequencing in a large family affected by an autosomal-dominant form of mild syndromic ID with ptosis, growth retardation, and hypotonia, and we identified an inherited 2 bp deletion causing a frameshift in BRPF1 (c.1052_1053del) in five affected family members. BRPF1 encodes a protein modifier of two histone acetyltransferases associated with ID: KAT6A (also known as MOZ or MYST3) and KAT6B (MORF or MYST4). The mRNA transcript was not significantly reduced in affected fibroblasts and most likely produces a truncated protein (p.Val351Glyfs∗8). The protein variant shows an aberrant cellular location, loss of certain protein interactions, and decreased histone H3K23 acetylation. We identified BRPF1 deletions or point mutations in six additional individuals with a similar phenotype. Deletions of the 3p25 region, containing BRPF1 and SETD5, cause a defined ID syndrome where most of the clinical features are attributed to SETD5 deficiency. We compared the clinical symptoms of individuals carrying mutations or small deletions of BRPF1 alone or SETD5 alone with those of individuals with deletions encompassing both BRPF1 and SETD5. We conclude that both genes contribute to the phenotypic severity of 3p25 deletion syndrome but that some specific features, such as ptosis and blepharophimosis, are mostly driven by BRPF1 haploinsufficiency.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Blefaroptose/genética , Genes Dominantes/genética , Histona Acetiltransferases/metabolismo , Deficiência Intelectual/genética , Mutação , Proteínas Nucleares/genética , Acetilação , Adulto , Blefarofimose/genética , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Feminino , Mutação da Fase de Leitura , Haploinsuficiência/genética , Humanos , Masculino , Metiltransferases/deficiência , Metiltransferases/genética , Hipotonia Muscular/genética , Fenótipo , Síndrome
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA