RESUMO
PURPOSE: Biallelic PIGN variants have been described in Fryns syndrome, multiple congenital anomalies-hypotonia-seizure syndrome (MCAHS), and neurologic phenotypes. The full spectrum of clinical manifestations in relation to the genotypes is yet to be reported. METHODS: Genotype and phenotype data were collated and analyzed for 61 biallelic PIGN cases: 21 new and 40 previously published cases. Functional analysis was performed for 2 recurrent variants (c.2679C>G p.Ser893Arg and c.932T>G p.Leu311Trp). RESULTS: Biallelic-truncating variants were detected in 16 patients-10 with Fryns syndrome, 1 with MCAHS1, 2 with Fryns syndrome/MCAHS1, and 3 with neurologic phenotype. There was an increased risk of prenatal or neonatal death within this group (6 deaths were in utero or within 2 months of life; 6 pregnancies were terminated). Incidence of polyhydramnios, congenital anomalies (eg, diaphragmatic hernia), and dysmorphism was significantly increased. Biallelic missense or mixed genotype were reported in the remaining 45 cases-32 showed a neurologic phenotype and 12 had MCAHS1. No cases of diaphragmatic hernia or abdominal wall defects were seen in this group except patient 1 in which we found the missense variant p.Ser893Arg to result in functionally null alleles, suggesting the possibility of an undescribed functionally important region in the final exon. For all genotypes, there was complete penetrance for developmental delay and near-complete penetrance for seizures and hypotonia in patients surviving the neonatal period. CONCLUSION: We have expanded the described spectrum of phenotypes and natural history associated with biallelic PIGN variants. Our study shows that biallelic-truncating variants usually result in the more severe Fryns syndrome phenotype, but neurologic problems, such as developmental delay, seizures, and hypotonia, present across all genotypes. Functional analysis should be considered when the genotypes do not correlate with the predicted phenotype because there may be other functionally important regions in PIGN that are yet to be discovered.
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Anormalidades Múltiplas , Defeitos Congênitos da Glicosilação , Epilepsia , Hérnia Diafragmática , Gravidez , Feminino , Humanos , Hipotonia Muscular/genética , Epilepsia/genética , Anormalidades Múltiplas/genética , Hérnia Diafragmática/genética , Convulsões/genética , Fenótipo , Estudos de Associação Genética , SíndromeRESUMO
BACKGROUND: Adaptor protein complex 4-associated hereditary spastic paraplegia (AP-4-HSP) is caused by pathogenic biallelic variants in AP4B1, AP4M1, AP4E1, and AP4S1. OBJECTIVE: The aim was to explore blood markers of neuroaxonal damage in AP-4-HSP. METHODS: Plasma neurofilament light chain (pNfL) and glial fibrillary acidic protein (GFAP) levels were measured in samples from patients and age- and sex-matched controls (NfL: n = 46 vs. n = 46; GFAP: n = 14 vs. n = 21) using single-molecule array assays. Patients' phenotypes were systematically assessed using the AP-4-HSP natural history study questionnaires, the Spastic Paraplegia Rating Scale, and the SPATAX disability score. RESULTS: pNfL levels increased in AP-4-HSP patients, allowing differentiation from controls (Mann-Whitney U test: P = 3.0e-10; area under the curve = 0.87 with a 95% confidence interval of 0.80-0.94). Phenotypic cluster analyses revealed a subgroup of individuals with severe generalized-onset seizures and developmental stagnation, who showed differentially higher pNfL levels (Mann-Whitney U test between two identified clusters: P = 2.5e-6). Plasma GFAP levels were unchanged in patients with AP-4-HSP. CONCLUSIONS: pNfL is a potential disease marker in AP-4-HSP and can help differentiate between phenotypic subgroups. © 2023 International Parkinson and Movement Disorder Society.
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Complexo 4 de Proteínas Adaptadoras , Paraplegia Espástica Hereditária , Humanos , Complexo 4 de Proteínas Adaptadoras/genética , Paraplegia Espástica Hereditária/genética , Filamentos Intermediários/metabolismo , Fenótipo , MutaçãoRESUMO
OBJECTIVE: Epilepsy is common in patients with PIGN diseases due to biallelic variants; however, limited epilepsy phenotyping data have been reported. We describe the epileptology of PIGN encephalopathy. METHODS: We recruited patients with epilepsy due to biallelic PIGN variants and obtained clinical data regarding age at seizure onset/offset and semiology, development, medical history, examination, electroencephalogram, neuroimaging, and treatment. Seizure and epilepsy types were classified. RESULTS: Twenty six patients (13 female) from 26 families were identified, with mean age 7 years (range = 1 month to 21 years; three deceased). Abnormal development at seizure onset was present in 25 of 26. Developmental outcome was most frequently profound (14/26) or severe (11/26). Patients presented with focal motor (12/26), unknown onset motor (5/26), focal impaired awareness (1/26), absence (2/26), myoclonic (2/26), myoclonic-atonic (1/26), and generalized tonic-clonic (2/26) seizures. Twenty of 26 were classified as developmental and epileptic encephalopathy (DEE): 55% (11/20) focal DEE, 30% (6/20) generalized DEE, and 15% (3/20) combined DEE. Six had intellectual disability and epilepsy (ID+E): two generalized and four focal epilepsy. Mean age at seizure onset was 13 months (birth to 10 years), with a lower mean onset in DEE (7 months) compared with ID+E (33 months). Patients with DEE had drug-resistant epilepsy, compared to 4/6 ID+E patients, who were seizure-free. Hyperkinetic movement disorder occurred in 13 of 26 patients. Twenty-seven of 34 variants were novel. Variants were truncating (n = 7), intronic and predicted to affect splicing (n = 7), and missense or inframe indels (n = 20, of which 11 were predicted to affect splicing). Seven variants were recurrent, including p.Leu311Trp in 10 unrelated patients, nine with generalized seizures, accounting for nine of the 11 patients in this cohort with generalized seizures. SIGNIFICANCE: PIGN encephalopathy is a complex autosomal recessive disorder associated with a wide spectrum of epilepsy phenotypes, typically with substantial profound to severe developmental impairment.
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Epilepsia Resistente a Medicamentos , Epilepsia , Deficiência Intelectual , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Feminino , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/genética , Fenótipo , Convulsões/genéticaRESUMO
Hypomyelinating leukodystrophies are genetic disorders characterized by insufficient myelin deposition during development. They are diagnosed on the basis of both clinical and MRI features followed by genetic confirmation. Here, we report on four unrelated affected individuals with hypomyelination and bi-allelic pathogenic variants in EPRS, the gene encoding cytoplasmic glutamyl-prolyl-aminoacyl-tRNA synthetase. EPRS is a bifunctional aminoacyl-tRNA synthetase that catalyzes the aminoacylation of glutamic acid and proline tRNA species. It is a subunit of a large multisynthetase complex composed of eight aminoacyl-tRNA synthetases and its three interacting proteins. In total, five different EPRS mutations were identified. The p.Pro1115Arg variation did not affect the assembly of the multisynthetase complex (MSC) as monitored by affinity purification-mass spectrometry. However, immunoblot analyses on protein extracts from fibroblasts of the two affected individuals sharing the p.Pro1115Arg variant showed reduced EPRS amounts. EPRS activity was reduced in one affected individual's lymphoblasts and in a purified recombinant protein model. Interestingly, two other cytoplasmic aminoacyl-tRNA synthetases have previously been implicated in hypomyelinating leukodystrophies bearing clinical and radiological similarities to those in the individuals we studied. We therefore hypothesized that leukodystrophies caused by mutations in genes encoding cytoplasmic aminoacyl-tRNA synthetases share a common underlying mechanism, such as reduced protein availability, abnormal assembly of the multisynthetase complex, and/or abnormal aminoacylation, all resulting in reduced translation capacity and insufficient myelin deposition in the developing brain.
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Alelos , Aminoacil-tRNA Sintetases/genética , Mutação/genética , Adolescente , Criança , Pré-Escolar , Evolução Fatal , Feminino , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
PIGT is one of over 29 glycosylphosphatidylinositol biosynthesis defect genes. Mutations cause genetically determined disorders characterized mainly by epilepsy with fever-sensitivity, central hypotonia, psychomotor delay and congenital malformations. The disease is known as multiple congenital anomalies-hypotonia-seizures syndrome 3 (MCAHS3) or glycosylphosphatidylinositol biosynthesis defect-7. Twenty-eight cases have been reported until today. We present seven novel Polish patients, all harboring 1582G>A variant in a homozygous or compound heterozygous state which seems to cause a milder phenotype of the disease.
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Aciltransferases/genética , Epilepsia/genética , Glicosilfosfatidilinositóis/deficiência , Deficiência Intelectual/genética , Transtornos Psicomotores/genética , Convulsões/genética , Criança , Pré-Escolar , Deficiências do Desenvolvimento/complicações , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Epilepsia/complicações , Epilepsia/patologia , Feminino , Citometria de Fluxo , Glicosilfosfatidilinositóis/genética , Homozigoto , Humanos , Lactente , Deficiência Intelectual/complicações , Deficiência Intelectual/patologia , Masculino , Mutação/genética , Malformações do Sistema Nervoso/complicações , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/patologia , Linhagem , Fenótipo , Polônia , Transtornos Psicomotores/patologia , Convulsões/complicações , Convulsões/patologiaRESUMO
OBJECTIVE: To comprehensively describe the natural history of vanishing white matter (VWM), aiming at improving counseling of patients/families and providing natural history data for future therapeutic trials. METHODS: We performed a longitudinal multicenter study among 296 genetically confirmed VWM patients. Clinical information was obtained via disease-specific clinical questionnaire, Health Utilities Index and Guy's Neurological Disability Scale assessments, and chart review. RESULTS: First disease signs occurred at a median age of 3 years (mode = 2 years, range = before birth to 54 years); 60% of patients were symptomatic before the age of 4 years. The nature of the first signs varied for different ages of onset. Overall, motor problems were the most common presenting sign, especially in children. Adolescent and adult onset patients were more likely to exhibit cognitive problems early after disease onset. One hundred two patients were deceased. Multivariate Cox regression analysis revealed a positive relation between age at onset and both preservation of ambulation and survival. Absence of stress-provoked episodes and absence of seizures predicted more favorable outcome. In patients with onset before 4 years, earlier onset was associated with more severe disability and higher mortality. For onset from 4 years on, disease course was generally milder, with a wide variation in severity. There were no significant differences for sex or for the 5 eIF2B gene groups. The results confirm the presence of a genotype-phenotype correlation. INTERPRETATION: The VWM disease spectrum consists of a continuum with extremely wide variability. Age at onset is a strong predictor for disease course. Ann Neurol 2018;84:274-288.
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Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/genética , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Leucoencefalopatias/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Most of the 19 mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs) involved in mitochondrial protein synthesis are already linked to specific entities, one of the exceptions being PARS2 mutations for which pathogenic significance is not finally validated. The aim of the study was to characterize the PARS2- related phenotype.Three siblings with biallelic PARS2 mutations presented from birth with infantile spasms, secondary microcephaly, and similar facial dysmorphy. Mental development was deeply impaired with speech absence and no eye contact. A dilated cardiomyopathy and multiorgan failure developed in childhood at the terminal stage, together with mitochondrial dysfunction triggered by valproate administration.Brain MRI showed progressive volume loss of the frontal lobes, both cortical and subcortical, with widening of the cortical sulci and frontal horns of the lateral ventricles. Hypoplasia of the corpus callosum and progressive demyelination were additional findings. Similar brain features were seen in three already reported PARS2 patients and seemed specific for this defect when compared with other mt-aaRSs defects (DARS2, EARS2, IARS2, and RARS2).Striking resemblance of the phenotype and Alpers-like brain MRI changes with predominance of frontal cerebral volume loss (FCVL-AS) in six patients from three families of different ethnicity with PARS2 mutations, justifies to distinguish the condition as a new disease entity.
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Alelos , Aminoacil-tRNA Sintetases/genética , Estudos de Associação Genética , Doenças Mitocondriais/diagnóstico , Doenças Mitocondriais/genética , Mutação , Fenótipo , Aminoacil-tRNA Sintetases/química , Biomarcadores , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Fácies , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Modelos Moleculares , Linhagem , Conformação Proteica , Sequenciamento do ExomaRESUMO
Metabolites of cerebrospinal biogenic amines (dopamine and serotonin)are an important tool in clinical research and diagnosis of children with neurotransmitter disorders. In this article we focused on finding relationships between the concentration of biogenic amine metabolites, age, and gender. We analyzed 148 samples from children with drug resistant seizures of unknown etiology and children with mild stable encephalopathy aged 0-18 years. A normal profile of biogenic amineswas found in 107 children and those children were enrolled to the study group. The CSF samples were analyzed by HPLC with an electrochemical detector. The concentrations of the dopamine and serotonin metabolites homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), respectively, were high at birth, gradually decreasing afterward until the 18 years of age. Nevertheless, the HVA/5-HIAA ratio did not vary with age, except in the children below 1 year of age. In the youngest group we observed a strong relationship between the HVA/5-HIAA ratio and age (r = 0.69, p < 0.001). There were no statistical differences in the level of both dopamine and serotonin metabolites between boys and girls, although a tread toward lower HVA and 5-HIAA in the boys was noticeable. Significant inter-gender differences in the level of HVA and 5-HIAA were noted only in the age-group of 1-4 years, with 5-HIAA being higher in the girls than boys (p = 0.004). In conclusion, the study revealed that the concentration of biogenic amine metabolites is age and sex dependent.
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Dopamina/líquido cefalorraquidiano , Convulsões/líquido cefalorraquidiano , Serotonina/líquido cefalorraquidiano , Adolescente , Fatores Etários , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Lactente , Masculino , Fatores SexuaisRESUMO
Alexander Disease (ALXDRD) is an autosomal dominant leukodystrophy caused by mutation in one allele of GFAP gene, encoding glial fibrillary acidic protein (GFAP). Most cases occur due to de novo. There are three clinical subtypes of ALXDRD: infantile, juvenile and adult form, but congenital form is also outlined. The disease's spectrum comprises of macrocephaly, progressive pyramidal signs, and seizures in congenital and infantile subtypes. Neuropathologically are enormous number of Rosenthal fibers (RF) mainly around vessels, in subependymal and subpial regions are found. The diagnosis is based on the typical findings on MRI: diffuse white mater lesions with frontal regions preponderance and possibly on the detection of the gene mutation. Here we present six Polish children affected of Alexander disease with congenital (1), infantile (4) and juvenile (1) form. Five of them were previously misdiagnosed as cerebral palsy or unspecific developmental delay; two patients had MRI because of another suspicion, before specific diagnosis was established. Molecular analysis performed in four cases confirmed mutations of GFAP gene; all mutation were de novo. The role of astroglia in brain is shortly reviewed.
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Doença de Alexander/genética , Doença de Alexander/patologia , Proteína Glial Fibrilar Ácida/genética , Bulbo/patologia , Doença de Alexander/classificação , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , PolôniaRESUMO
Neuronal ceroid lipofuscinoses (NCLs) are a growing group of neurodegenerative storage diseases, in which specific features are sought to facilitate the creation of a universal diagnostic algorithm in the future. In our ultrastructural studies, the group of NCLs was represented by the CLN2 disease caused by a defect in the TPP1 gene encoding the enzyme tripeptidyl-peptidase 1. A 3.5-year-old girl was affected by this disease. Due to diagnostic difficulties, the spectrum of clinical, enzymatic, and genetic tests was extended to include analysis of the ultrastructure of cells from a rectal biopsy. The aim of our research was to search for pathognomonic features of CLN2 and to analyse the mitochondrial damage accompanying the disease. In the examined cells of the rectal mucosa, as expected, filamentous deposits of the curvilinear profile (CVP) type were found, which dominated quantitatively. Mixed deposits of the CVP/fingerprint profile (FPP) type were observed less frequently in the examined cells. A form of inclusions of unknown origin, not described so far in CLN2 disease, were wads of osmophilic material (WOMs). They occurred alone or co-formed mixed deposits. In addition, atypically damaged mitochondria were observed in muscularis mucosae. Their deformed cristae had contact with inclusions that looked like CVPs. Considering the confirmed role of the c subunit of the mitochondrial ATP synthase in the formation of filamentous lipopigment deposits in the group of NCLs, we suggest the possible significance of other mitochondrial proteins, such as mitochondrial contact site and cristae organizing system (MICOS), in the formation of these deposits. The presence of WOMs in the context of searching for ultrastructural pathognomonic features in CLN2 disease also requires further research.
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Dipeptidil Peptidases e Tripeptidil Peptidases , Corpos de Inclusão , Mitocôndrias , Lipofuscinoses Ceroides Neuronais , Tripeptidil-Peptidase 1 , Lipofuscinoses Ceroides Neuronais/patologia , Lipofuscinoses Ceroides Neuronais/genética , Humanos , Feminino , Pré-Escolar , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Corpos de Inclusão/patologia , Corpos de Inclusão/ultraestrutura , Biópsia , Reto/patologia , Serina Proteases/genética , Aminopeptidases/genéticaRESUMO
BACKGROUND: KIF1A (kinesin family member 1A)-related disorders encompass a variety of diseases. KIF1A variants are responsible for autosomal recessive and dominant spastic paraplegia 30 (SPG, OMIM610357), autosomal recessive hereditary sensory and autonomic neuropathy type 2 (HSN2C, OMIM614213), and autosomal dominant neurodegeneration and spasticity with or without cerebellar atrophy or cortical visual impairment (NESCAV syndrome), formerly named mental retardation type 9 (MRD9) (OMIM614255). KIF1A variants have also been occasionally linked with progressive encephalopathy with brain atrophy, progressive neurodegeneration, PEHO-like syndrome (progressive encephalopathy with edema, hypsarrhythmia, optic atrophy), and Rett-like syndrome. MATERIALS AND METHODS: The first Polish patients with confirmed heterozygous pathogenic and potentially pathogenic KIF1A variants were analyzed. All the patients were of Caucasian origin. Five patients were females, and four were males (female-to-male ratio = 1.25). The age of onset of the disease ranged from 6 weeks to 2 years. RESULTS: Exome sequencing identified three novel variants. Variant c.442G>A was described in the ClinVar database as likely pathogenic. The other two novel variants, c.609G>C; p.(Arg203Ser) and c.218T>G, p.(Val73Gly), were not recorded in ClinVar. CONCLUSIONS: The authors underlined the difficulties in classifying particular syndromes due to non-specific and overlapping signs and symptoms, sometimes observed only temporarily.
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Doenças Neurodegenerativas , Espasmos Infantis , Paraplegia Espástica Hereditária , Humanos , Masculino , Feminino , Lactente , Polônia , Cinesinas/genética , Paraplegia Espástica Hereditária/patologia , AtrofiaRESUMO
The development of midbrain dopamine (DA) neurons is regulated by several transcription factors, including Nurr1, Wnt1, Lmx1a/1b, En1, En2, Foxa1, Foxa2, and Pitx3. PITX3 is an upstream co-activator of the TH (tyrosine hydroxylase) promoter. Pitx3(-/-) mice have a selective loss of dopaminergic neurons in the substantia nigra and ventral tegmental area, leading to the significantly reduced DA levels in the nigrostriatal pathway and in the dorsal striatum and manifest anomalous striatum-dependent cognitive impairment and neurobehavioral activity. Treatment with L-DOPA, dopamine, or dopamine receptor agonists in these mice reversed several of their sensorimotor impairments. Heterozygous missense mutations in PITX3 have been reported in patients with autosomal dominant congenital cataract and anterior segment (ocular) mesenchymal dysgenesis (ASMD) whereas homozygous missense mutations have been found in patients with microphthalmia and neurological impairment. Using a clinical oligonucleotide array comparative genomic hybridization (aCGH), we have identified an â¼317 kb hemizygous deletion in 10q24.32, involving PITX3 in a 17-year-old male with a Smith-Magenis syndrome-like phenotype, including mild intellectual impairment, sleep disturbance, hyperactivity, and aggressive and self-destructive behavior. Interestingly, no eye anomalies were found in our patient. Analysis of neurotransmitters in his cerebrospinal fluid revealed an absence of L-DOPA and significantly decreased levels of catecholamine metabolites. Importantly, L-DOPA treatment of our patient has led to mild mitigation of his aggressive behavior and mild improvement of his attention span, extended time periods of concentration, and better sleep.
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Neurônios Dopaminérgicos/metabolismo , Proteínas de Homeodomínio/genética , Levodopa/uso terapêutico , Comportamento Autodestrutivo/genética , Deleção de Sequência , Síndrome de Smith-Magenis/genética , Síndrome de Smith-Magenis/prevenção & controle , Fatores de Transcrição/genética , Adolescente , Adulto , Hibridização Genômica Comparativa , Análise Citogenética , DNA/genética , Dopaminérgicos/líquido cefalorraquidiano , Dopaminérgicos/uso terapêutico , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Levodopa/líquido cefalorraquidiano , Levodopa/deficiência , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Síndrome de Smith-Magenis/psicologia , Adulto JovemRESUMO
Copy-number variants (CNVs) collectively represent an important cause of neurodevelopmental disorders such as developmental delay (DD)/intellectual disability (ID), autism, and epilepsy. In contrast to DD/ID, for which the application of microarray techniques enables detection of pathogenic CNVs in -10-20% of patients, there are only few studies of the role of CNVs in epilepsy and genetic etiology in the vast majority of cases remains unknown. We have applied whole-genome exon-targeted oligonucleotide array comparative genomic hybridization (array CGH) to a cohort of 102 patients with various types of epilepsy with or without additional neurodevelopmental abnormalities. Chromosomal microarray analysis revealed 24 non-polymorphic CNVs in 23 patients, among which 10 CNVs are known to be clinically relevant. Two rare deletions in 2q24.1q24.3, including KCNJ3 and 9q21.13 are novel pathogenic genetic loci and 12 CNVs are of unknown clinical significance. Our results further support the notion that rare CNVs can cause different types of epilepsy, emphasize the efficiency of detecting novel candidate genes by whole-genome array CGH, and suggest that the clinical application of array CGH should be extended to patients with unexplained epilepsies.
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Deficiências do Desenvolvimento/genética , Epilepsia/genética , Genoma Humano , Adolescente , Transtorno Autístico/complicações , Transtorno Autístico/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa/métodos , Variações do Número de Cópias de DNA , Deficiências do Desenvolvimento/complicações , Epilepsia/complicações , Éxons , Dosagem de Genes , Humanos , Lactente , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , MasculinoRESUMO
We report on the first Polish patient diagnosed with the Aicardi-Goutières syndrome 5 (AGS5). AGS is caused by mutations in one of 9 genes (TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR, IFIH, LSM11, RNU7-1) which stimulate the type I interferon response. The diagnosis was confirmed by identifying a compound heterozygous mutation p.(Phe165Ser)/p.(Gln235*) in the SAMHD1 gene using whole-exome sequencing. The cystic lesions in the temporal lobes are an uncommon finding in the presented patient carrying a SAMHD1 mutation. Reporting new cases expands the range of phenotypes and plays the crucial role in understanding the AGS pathogenesis and creates new therapy approaches.
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PURPOSE: Mutations in the CDKL5 gene have been associated with an X-linked dominant early infantile epileptic encephalopathy-2. The clinical presentation is usually of severe encephalopathy with refractory seizures and Rett syndrome (RTT)-like phenotype. We attempted to assess the role of mosaic intragenic copy number variation in CDKL5. METHODS: We have used comparative genomic hybridization with a custom-designed clinical oligonucleotide array targeting exons of selected disease and candidate genes, including CDKL5. RESULTS: We have identified mosaic exonic deletions of CDKL5 in one male and two females with developmental delay and medically intractable seizures. These three mosaic changes represent 60% of all deletions detected in 12,000 patients analyzed by array comparative genomic hybridization and involving the exonic portion of CDKL5. CONCLUSION: We report the first case of an exonic deletion of CDKL5 in a male and emphasize the importance of underappreciated mosaic exonic copy number variation in patients with early-onset seizures and RTT-like features of both genders.
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Éxons/genética , Mosaicismo , Proteínas Serina-Treonina Quinases/genética , Convulsões/genética , Deleção de Sequência/genética , Idade de Início , Criança , Pré-Escolar , Cromossomos Humanos X/genética , Feminino , Ordem dos Genes , Humanos , Lactente , MasculinoRESUMO
Developmental and epileptic encephalopathies (DEE) constitute an expanding group of severely disabling and, most frequently, drug-resistant disorders starting in the first year of life. Among them, there is DEE43, caused by dominant mutations in the GABRB3 gene. We present first neuropathological findings in a novel, molecularly confirmed case with the fatal course. The neuropathological analysis revealed co-existing developmental anomalies and retardation of myelination resulting from disturbed early brain growth as well as lesions caused by epileptic hypoxic-ischemic episodes. Developmental anomalies included misplaced neurons in the cerebellar white matter, heterotopic neurons in the cortical molecular layer and in the molecular layer of the hippocampal dentate gyrus, dysmorphic cerebellar dentate nuclei and inferior olivary nuclei in the medulla oblongata. The migrational and maturational disorders leading to the neuronal network dysfunction could be the cause of both the lack of development and the ineffectiveness of antiepileptic treatment in children affected by DEE. Giving the presented neuropathological description and based on the literature, we discuss the pathomechanism of the disease, to improve current understanding of both the lack of development and the ineffectiveness of treatment of affected children.
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Encefalopatias , Eletroencefalografia , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Encefalopatias/tratamento farmacológico , Criança , Deficiências do Desenvolvimento/tratamento farmacológico , HumanosRESUMO
Increased activity of dipeptidyl peptidase IV (DPP-IV) was reported earlier in patients with different types of mucopolysaccharidoses. DPP-IV (also known as CD26 lymphocyte T surface antigen) is a transmembrane protein showing protease activity. This enzyme displays various functions in the organism and plays an important role in multiple processes like glucose metabolism, nociception, cell-adhesion, psychoneuroendocrine regulation, immune response and cardiovascular adaptation. In order to evaluate DPP-IV in lysosomal storage diseases (LSD), we examined its activity in plasma samples from 307 patients affected with 24 different LSDs and in 75 control persons. Our results revealed elevated DPP-IV activity especially in individuals affected with mucolipidosis II/III, alpha-mannosidosis, and mucopolysaccharidoses types III, II, and I (p < 0.05). In other LSDs the DPP-IV activity was still significantly increased, but to a lesser extent. In patients with Gaucher disease, ceroid lipofuscinosis type 1 (CLN1), Niemann-Pick disease type C and A, Krabbe and Pompe diseases, gangliosidosis GM2 and metachromatic leukodystrophy discreet or no changes in DPP-IV activity were observed. DPP-IV may serve as a first-tier diagnostic procedure or additional biochemical analysis in recognizing patients with some LSDs. DPP-IV may become an object of basic research for a better understanding of LSDs.
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CONTEXT: 4H or POLR3-related leukodystrophy is an autosomal recessive disorder typically characterized by hypomyelination, hypodontia, and hypogonadotropic hypogonadism, caused by biallelic pathogenic variants in POLR3A, POLR3B, POLR1C, and POLR3K. The endocrine and growth abnormalities associated with this disorder have not been thoroughly investigated to date. OBJECTIVE: To systematically characterize endocrine abnormalities of patients with 4H leukodystrophy. DESIGN: An international cross-sectional study was performed on 150 patients with genetically confirmed 4H leukodystrophy between 2015 and 2016. Endocrine and growth abnormalities were evaluated, and neurological and other non-neurological features were reviewed. Potential genotype/phenotype associations were also investigated. SETTING: This was a multicenter retrospective study using information collected from 3 predominant centers. PATIENTS: A total of 150 patients with 4H leukodystrophy and pathogenic variants in POLR3A, POLR3B, or POLR1C were included. MAIN OUTCOME MEASURES: Variables used to evaluate endocrine and growth abnormalities included pubertal history, hormone levels (estradiol, testosterone, stimulated LH and FSH, stimulated GH, IGF-I, prolactin, ACTH, cortisol, TSH, and T4), and height and head circumference charts. RESULTS: The most common endocrine abnormalities were delayed puberty (57/74; 77% overall, 64% in males, 89% in females) and short stature (57/93; 61%), when evaluated according to physician assessment. Abnormal thyroid function was reported in 22% (13/59) of patients. CONCLUSIONS: Our results confirm pubertal abnormalities and short stature are the most common endocrine features seen in 4H leukodystrophy. However, we noted that endocrine abnormalities are typically underinvestigated in this patient population. A prospective study is required to formulate evidence-based recommendations for management of the endocrine manifestations of this disorder.
Assuntos
RNA Polimerases Dirigidas por DNA/genética , Doenças do Sistema Endócrino/genética , Transtornos do Crescimento/genética , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Doenças Mitocondriais/genética , Adolescente , Adulto , Variação Biológica da População , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Doenças do Sistema Endócrino/epidemiologia , Doenças do Sistema Endócrino/etiologia , Feminino , Heterogeneidade Genética , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/etiologia , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/complicações , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/epidemiologia , Humanos , Hipogonadismo/epidemiologia , Hipogonadismo/etiologia , Lactente , Recém-Nascido , Masculino , Doenças Mitocondriais/complicações , Doenças Mitocondriais/epidemiologia , Mutação , RNA Polimerase III/genética , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: Molecular studies allow to study background of many epilepsy types but qualification for genotyping is not easy, especially in initial stages of severe encephalopathy in newborns and infants. One of them is a type 2 severe epileptic encephalopathy (EIEE2), caused by dominant mutation in CDKL5 gene (Xp22.3). In this type of encephalopathy appearing mainly in females, treatment resistant epileptic seizures occur in the first two months of life, they are polymorphic-generalized or focal. Psychomotor development is significantly impaired and in course of time phenotype shows similarities to an Angelman syndrome or an atypical severe form of Rett syndrome. Correlation between clinical status and repeating EEG might be a diagnostic indicator for looking for CDKL5 gene mutation. AIM: We report a case of 3.5 years old girl with refractory epilepsy and dysmorphia like in Angelman syndrome. Mutation in CDKL5 gene was supposed during clinical observation and EEG examination and finally was confirmed. CASE REPORT: Family history and fetal & perinatal history were negative. The patient suffered from treatment resistant polymorphic epileptic seizures appearing from 3 months of life. Psychomotor impairment, significant flaccidity and microcephaly were observed from early infant period. Additionally, pale complexion, always opened mouth, protruding tongue, prognathia, wide-spaced teeth, frequent laughter/smiling were seen. Brain MRI (including MRS) was normal. Repeating EEG showed evolution from normal during infantile spasms to multifocal discharges and loss of sleep spindles. Metabolic disorders, Angelman and Rett syndromes were excluded. Finally, mutation in CDKL5 gene was confirmed at the age of 2.5 into genetic counseling. CONCLUSIONS: There is a need to correlate phenotype features and sequential EEG and epileptic seizures evolution to determine indication for genotyping. Genetic testing looking for CDKL5 mutation is indicated in each female child with impaired psychomotor development, refractory epilepsy with early onset polymorphic seizures and clinical & EEG phenotype of atypical Rett/Angelman syndrome.