Epilepsie jsou heterogenní skupinou onemocnění. Příčinou jsou strukturální vývojové vady mozku, metabolická onemocnění a v poslední době výrazně přibylo objevů řady genů, jejichž mutace způsobují epilepsie. V projektu budou využity metody molekulární genetiky - masivní paralelní sekvenování včetně exomového sekvenování – pro objasnění příčin dětských epilepsií a epileptických encefalopatií. Takové možnosti dosud nejsou v ČR dostupné. V projektu bude pomocí metody HaloPlex připraven panel genů, jejichž poruchy jsou spojeny s epilepsiemi dětského věku (již více než 100 genů). Cílem je vyšetřit cca. 100-150 pacientů (převážně z našeho Centra pro epilepsie) s těžkou epilepsií, kteří nemají objasněnou etiologii a mají negativní MRI mozku. Výsledky genetického testování budou interpretovány se zkušeným epileptologem v kontextu klinických příznaků a rodinné anamnézy. V naší laboratoři již máme velmi dobré zkušenosti s využitím sekvenování nové generace u geneticky heterogenního onemocnění (dědičné neuropatie). Výsledky budou mít velký význam pro klinickou praxi a zlepší péči o pacienty.; We will use massive parallel sequencing (MPS – targeted as well as whole exome) for elucidation of causes of severe childhood epilepsies and epileptic encephalopathies. This approach is not yet available in the Czech Republic. A large cohort of patients with unknown cause of non-lesional epilepsy is available at our Centre for epilepsies. We will focus on epileptic encephalopathies, severe childhood epilepsies and familial epileptic syndromes and syndromes with epilepsy. We also have enough experience and equipment for data processing and filtering from MPS in other neurological disorders. In selected patients a panel of all (about 100) relevant known genes yet related to monogenic early childhood epilepsies and epileptic encephalopathies will be examined by the HaloPlex MPS method. About 50 patients per year will be tested. Results will be interpreted by experienced epileptologists according to clinical data and family history. The results will improve our understanding of the aethiology of epilepsies and improve Czech healthcare including personalized therapy.

• MeSH
• dítě MeSH
• epilepsie diagnóza   MeSH
• mutace MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• dítě MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• neurologie
• genetika, lékařská genetika
• pediatrie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

PURPOSE: Variants in IQSEC2, escaping X inactivation, cause X-linked intellectual disability with frequent epilepsy in males and females. We aimed to investigate sex-specific differences. METHODS: We collected the data of 37 unpublished patients (18 males and 19 females) with IQSEC2 pathogenic variants and 5 individuals with variants of unknown significance and reviewed published variants. We compared variant types and phenotypes in males and females and performed an analysis of IQSEC2 isoforms. RESULTS: IQSEC2 pathogenic variants mainly led to premature truncation and were scattered throughout the longest brain-specific isoform, encoding the synaptic IQSEC2/BRAG1 protein. Variants occurred de novo in females but were either de novo (2/3) or inherited (1/3) in males, with missense variants being predominantly inherited. Developmental delay and intellectual disability were overall more severe in males than in females. Likewise, seizures were more frequently observed and intractable, and started earlier in males than in females. No correlation was observed between the age at seizure onset and severity of intellectual disability or resistance to antiepileptic treatments. CONCLUSION: This study provides a comprehensive overview of IQSEC2-related encephalopathy in males and females, and suggests that an accurate dosage of IQSEC2 at the synapse is crucial during normal brain development.

• MeSH
• fenotyp MeSH
• kojenec MeSH
• lidé MeSH
• mentální retardace epidemiologie   genetika   patofyziologie   MeSH
• mozek růst a vývoj   metabolismus   MeSH
• mutace MeSH
• nemoci mozku epidemiologie   genetika   patofyziologie   MeSH
• novorozenec MeSH
• pohlavní dimorfismus MeSH
• protein - isoformy genetika   MeSH
• rodokmen MeSH
• výměnné faktory guaninnukleotidů genetika   MeSH
• záchvaty epidemiologie   genetika   patofyziologie   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: De novo mutations in PURA have recently been described to cause PURA syndrome, a neurodevelopmental disorder characterised by severe intellectual disability (ID), epilepsy, feeding difficulties and neonatal hypotonia. OBJECTIVES: To delineate the clinical spectrum of PURA syndrome and study genotype-phenotype correlations. METHODS: Diagnostic or research-based exome or Sanger sequencing was performed in individuals with ID. We systematically collected clinical and mutation data on newly ascertained PURA syndrome individuals, evaluated data of previously reported individuals and performed a computational analysis of photographs. We classified mutations based on predicted effect using 3D in silico models of crystal structures of Drosophila-derived Pur-alpha homologues. Finally, we explored genotype-phenotype correlations by analysis of both recurrent mutations as well as mutation classes. RESULTS: We report mutations in PURA (purine-rich element binding protein A) in 32 individuals, the largest cohort described so far. Evaluation of clinical data, including 22 previously published cases, revealed that all have moderate to severe ID and neonatal-onset symptoms, including hypotonia (96%), respiratory problems (57%), feeding difficulties (77%), exaggerated startle response (44%), hypersomnolence (66%) and hypothermia (35%). Epilepsy (54%) and gastrointestinal (69%), ophthalmological (51%) and endocrine problems (42%) were observed frequently. Computational analysis of facial photographs showed subtle facial dysmorphism. No strong genotype-phenotype correlation was identified by subgrouping mutations into functional classes. CONCLUSION: We delineate the clinical spectrum of PURA syndrome with the identification of 32 additional individuals. The identification of one individual through targeted Sanger sequencing points towards the clinical recognisability of the syndrome. Genotype-phenotype analysis showed no significant correlation between mutation classes and disease severity.

• MeSH
• abnormality očí genetika   MeSH
• DNA vazebné proteiny chemie   genetika   MeSH
• genetické asociační studie MeSH
• lidé MeSH
• mentální retardace genetika   MeSH
• mutace * MeSH
• novorozenec MeSH
• obličej abnormality   MeSH
• proteiny Drosophily chemie   genetika   MeSH
• strukturní homologie proteinů MeSH
• svalová hypotonie etiologie   genetika   MeSH
• syndrom MeSH
• těhotenství MeSH
• transkripční faktory chemie   genetika   MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels control neuronal excitability and their dysfunction has been linked to epileptogenesis but few individuals with neurological disorders related to variants altering HCN channels have been reported so far. In 2014, we described five individuals with epileptic encephalopathy due to de novo HCN1 variants. To delineate HCN1-related disorders and investigate genotype-phenotype correlations further, we assembled a cohort of 33 unpublished patients with novel pathogenic or likely pathogenic variants: 19 probands carrying 14 different de novo mutations and four families with dominantly inherited variants segregating with epilepsy in 14 individuals, but not penetrant in six additional individuals. Sporadic patients had epilepsy with median onset at age 7 months and in 36% the first seizure occurred during a febrile illness. Overall, considering familial and sporadic patients, the predominant phenotypes were mild, including genetic generalized epilepsies and genetic epilepsy with febrile seizures plus (GEFS+) spectrum. About 20% manifested neonatal/infantile onset otherwise unclassified epileptic encephalopathy. The study also included eight patients with variants of unknown significance: one adopted patient had two HCN1 variants, four probands had intellectual disability without seizures, and three individuals had missense variants inherited from an asymptomatic parent. Of the 18 novel pathogenic missense variants identified, 12 were associated with severe phenotypes and clustered within or close to transmembrane domains, while variants segregating with milder phenotypes were located outside transmembrane domains, in the intracellular N- and C-terminal parts of the channel. Five recurrent variants were associated with similar phenotypes. Using whole-cell patch-clamp, we showed that the impact of 12 selected variants ranged from complete loss-of-function to significant shifts in activation kinetics and/or voltage dependence. Functional analysis of three different substitutions altering Gly391 revealed that these variants had different consequences on channel biophysical properties. The Gly391Asp variant, associated with the most severe, neonatal phenotype, also had the most severe impact on channel function. Molecular dynamics simulation on channel structure showed that homotetramers were not conducting ions because the permeation path was blocked by cation(s) strongly complexed to the Asp residue, whereas heterotetramers showed an instantaneous current component possibly linked to deformation of the channel pore. In conclusion, our results considerably expand the clinical spectrum related to HCN1 variants to include common generalized epilepsy phenotypes and further illustrate how HCN1 has a pivotal function in brain development and control of neuronal excitability.

• MeSH
• CHO buňky MeSH
• Cricetulus MeSH
• dítě MeSH
• dospělí MeSH
• draslíkové kanály genetika   MeSH
• elektrická stimulace MeSH
• epilepsie generalizovaná genetika   MeSH
• genetické asociační studie MeSH
• hyperpolarizační iontové kanály řízené cyklickými nukleotidy genetika   MeSH
• kojenec MeSH
• křeče u dětí genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• membránové potenciály genetika   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• molekulární modely MeSH
• mutace genetika   MeSH
• mutageneze cílená metody   MeSH
• předškolní dítě MeSH
• senioři MeSH
• zvířata MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• senioři MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Rozvoj v oblasti molekulárně genetických metod vede k nárůstu objasnění genetických příčin epilepsií, zejména závažných epilepsií dětského věku asociovaných s komorbiditami. Pro správnou interpretaci nálezů je nezbytná spolupráce neurologa, klinického genetika a molekulárního biologa.

Current progress in genetic technologies increases the detection rate of genetic causes of epilepsies, especially of early infantileonset epilepsies associated with comorbidities. Cooperation of neurologists with clinical geneticists and molecular biologist isessential for correct interpretation of the results.

• MeSH
• diagnostické techniky molekulární metody   MeSH
• epilepsie etiologie   genetika   MeSH
• epileptické syndromy genetika   MeSH
• genetické testování metody   MeSH
• hybridizace in situ fluorescenční MeSH
• karyotypizace MeSH
• lidé MeSH
• srovnávací genomová hybridizace metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

Background: With only 11 patients reported, 5p tetrasomy belongs to rare postnatal findings. Most cases are due to small supernumerary marker chromosomes (sSMCs) or isochromosomes. The patients share common but unspecific symptoms such as developmental delay, seizures, ventriculomegaly, hypotonia, and fifth finger clinodactyly. Simple interstitial duplications leading to trisomies of parts of 5p are much more frequent and better described. Duplications encompassing 5p13.2 cause a defined syndrome with macrocephaly, distinct facial phenotype, heart defects, talipes equinovarus, feeding difficulties, respiratory distress and anomalies of the central nervous system, developmental delay and hypotonia. Case presentation: We present a boy with dysmorphic features, developmental delay, intellectual disability and congenital anomalies, and a mosaic sSMC inv dup(5)(p15.33p15.1). He is the fourth and the oldest reported patient with distal 5p tetrasomy. His level of mosaicism was significantly different in lymphocytes (13.2%) and buccal cells (64.7%). The amplification in our patient is smaller than that in the three previously published patients but the only phenotype difference is the absence of seizures in our patient. Conclusions: Our observations indicate that for the assessment of prognosis, especially with respect to intellectual functioning, the level of mosaicism could be more important than the extent of amplification and the number of extra copies. Evaluation of the phenotypical effect of rare chromosomal aberrations is challenging and each additional case is valuable for refinement of the genotype-phenotype correlation. Moreover, our patient demonstrates that if the phenotype is severe and if the level of sSMC mosaicism is low in lymphocytes, other tissues should be tested.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Epilepsy is a heterogeneous disease with a broad phenotypic spectrum and diverse genotypes. A significant proportion of epilepsies has a genetic aetiology. In our study, a custom designed gene panel with 112 genes known to be associated with epilepsies was used. In total, one hundred and fifty-one patients were tested (86 males / 65 females). RESULTS: In our cohort, the highest probability for the identification of the cause of the disease was for patients with a seizure onset within the first four weeks of life (61.9% clarification rate) - about two times more than other groups. The level of statistical significance was determined using a chi-square analysis. From 112 genes included in the panel, suspicious and rare variants were found in 53 genes (47.3%). Among the 151 probands included in the study we identified pathogenic variants in 39 patients (25.8%), likely pathogenic variants in three patients (2%), variants of uncertain significance in 40 patients (26.5%) and likely benign variants in 69 patients (45.7%). CONCLUSION: Our report shows the utility of diagnostic genetic testing of severe childhood epilepsies in a large cohort of patients with a diagnostic rate of 25.8%. A gene panel can be considered as a method of choice for the detection of pathogenic variants within patients with unknown origin of early onset severe epilepsy.

• MeSH
• dítě MeSH
• epilepsie genetika   MeSH
• genetická predispozice k nemoci genetika   MeSH
• kojenec MeSH
• křeče u dětí genetika   MeSH
• lidé MeSH
• mutace MeSH
• předškolní dítě MeSH
• rozdělení chí kvadrát MeSH
• záchvaty genetika   MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Recently, a study providing insight into GABRB3 mutational spectrum was published (Møller et al 2017). The authors report considerable pleiotropy even for single mutations and were not able to identify any genotype-phenotype correlations. METHODS: The proband (twin B) was referred for massively parallel sequencing of epilepsy-related gene panel because of hypotonia and neonatal seizures. The revealed variant was confirmed with Sanger sequencing in the proband and the twin A, and both parents were tested for the presence of the variant. RESULTS: We report a case of epilepsy of infancy with migrating focal seizures (EIMFS) of neonatal onset in monozygotic twins with a de novo novel GABRB3 variant p.Thr281Ala. The variant has a uniform presentation on an identical genomic background. In addition, early seizure-onset epilepsy associated with GABRB3 mutation has been until now described only for the p.Leu256Gln variant in the GABRB3 (Møller et al 2017, Myers et al 2016) located in the transmembrane domain just as the p.Thr281Ala variant described here. CONCLUSION: De novo GABRB3 mutations may cause neonatal-onset EIMFS with early-onset hypotonia, respiratory distress, and severe developmental delay.

• MeSH
• dvojčata monozygotní genetika   MeSH
• epilepsie farmakoterapie   epidemiologie   genetika   MeSH
• kojenec MeSH
• lidé MeSH
• mutace * MeSH
• nemoci u dvojčat farmakoterapie   epidemiologie   genetika   MeSH
• novorozenec MeSH
• receptory GABA-A genetika   MeSH
• věk při počátku nemoci MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH

• MeSH
• chloralhydrát aplikace a dávkování   farmakologie   MeSH
• draslíkový kanál KCNQ2 genetika   MeSH
• hypnotika a sedativa aplikace a dávkování   farmakologie   MeSH
• křeče u dětí * farmakoterapie   genetika   patofyziologie   MeSH
• lidé MeSH
• mladiství MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• ženské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• kazuistiky MeSH

The SPAST gene has a major role in hereditary spastic paraplegias (HSPs). This is the first report mapping characteristics of the SPAST gene in a large cohort of Czech HSP patients. All 17 coding exons of the SPAST gene were Sanger sequenced in 327 patients from 263 independent families with suspected uncomplicated HSP. The selected 126 independent patients, without mutation in the SPAST gene after Sanger sequencing, were subsequently tested by Multiplex Ligation-dependent Probe Amplification (MLPA) assay for large deletions or copy number variations affecting the SPAST gene. Among the 263 independent patients, 35 different, small mutations in 44 patients were found. Twenty-one mutations are novel with the majority of frameshift mutations. Seven mutations were found in more than one family. The age at onset ranged between preschool childhood and the fifth decade with inter- and intra-familiar differences. SPAST small mutations were detected in 16.7% (44/263) of independent tested patients. Mutations in the SPAST gene were found more frequently in familial cases (with affected relatives). Mutation were found in 31.9% (29/91 familial tested) in the familial patient group, whereas in the sporadic patient group, mutations were found in only 4.7% of cases (5/106 sporadic cases). Among SPAST-positive patients, 65.9% (29/44) were familial but only 11.4% (5/44) were sporadic. MLPA testing revealed four large deletions in four independent patients, all in familial-positive cases. Mutations in the SPAST gene are 5.8 × more frequent in familial than in sporadic cases. Large deletions were found only in familial patients. Diagnostic testing of the SPAST gene is useful only in positive family history patients not in sporadic cases.

• MeSH
• adenosintrifosfatasy genetika   MeSH
• alely MeSH
• dospělí MeSH
• exony MeSH
• fenotyp MeSH
• genotyp MeSH
• introny MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• polymorfismus genetický MeSH
• rodokmen MeSH
• sekvenční analýza DNA MeSH
• sekvenční delece MeSH
• spastická paraplegie dědičná diagnóza   genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH