Vzácná onemocnění jsou skupinou více než 8000 chorob. Sedmdesát pět procent vzácných onemocnění se projevuje v dětském věku a 30% postižených dětí umírá do 5-ti let věku. Vzácná onemocnění tak významně snižují kvalitu života pacientů a mají významný sociální dopad na postižené rodiny. Molekulární podstata byla doposud objasněna u méně než poloviny těchto onemocnění a diagnóza je většinou určena jen v malém počtu jednotlivých případů. Správná diagnóza je přitom nezbytná pro léčbu a další sledování pacienta, ale i pro genetické poradenství a prevenci v rodinách. V tomto projektu využijeme moderních genomických a molekulárně biologických metod a pokusíme se určit diagnózu a objasnit etiologii nemoci ve skupině ~ 100 dětí a jejich rodin se vzácným geneticky podmíněným onemocněním neznámé příčiny. Výzkum by měl též odhalit biologické funkce kauzálních genů, definovat vhodné terapeutické cíle a postupy, objasnit základní biologické principy a patofyziologické mechanismy u člověka, případně definovat geny a metabolické dráhy účastné v rozvoji komplexních onemocnění.; Rare diseases comprise a group of more than 8000 disorders. Seventy-five per cent of rare diseases affect children, and about 30% of them die before the age of five year. This decrease quality of life for each affected individual, and have a significant social impact on affected families. Molecular basis have been identified in less than half of these disorders and the diagnosis is usually established in only a small proportion of patients. Accurate diagnosis is critical for treatment and surveillance of each patient, and for genetic counseling and prevention in families. We will use modern genomic and molecular biology techniques to establish the genetic diagnosis and etiology of the disorder in a group of ~ 100 children with rare genetic diseases of unknown origin. The research will explain biological functions of disease causing genes and identify novel therapeutic targets and approaches. Our research may also provide insights about basic biological principles and pathophysiologic processes in humans and identify genes and pathways involved in the etiology of common diseases.

• MeSH
• diagnostické techniky molekulární MeSH
• dítě MeSH
• genetická predispozice k nemoci etiologie   MeSH
• genom lidský MeSH
• genomika MeSH
• prognóza MeSH
• vzácné nemoci etiologie   MeSH
• Check Tag
• dítě MeSH

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

Vzácná onemocnění představují skupinu 8000 různých nemocí postihujících zhruba 8 % populace. Studium genomů významně zvyšuje znalosti o genetické variabilitě člověka a pomocí efektivního sdílení dat v mezinárodních registrech umožňuje kauzální diagnostiku širokého spektra vzácných onemocnění u cca 55-65 % nemocných. Diagnostika zbývajících pacientů závisí na nových technologiích a konceptech studia lidských genomů, které se zaměřují na genetickou a funkční analýzu genetických variant a jejich kombinací s cílem rozpoznat genetickou heterogenitu jednotlivých nemocí, přítomnost somatického mozaicismu, existenci fenokopií, různé penetrance a expresivity jednotlivých mutací a oligogenních typů dědičnosti. Stoupá význam analýz nekódujících oblastí lidské DNA a studium jejího vlivu na transkripci a strukturu mRNA a analýzy repetitivních a homologních oblastí lidského genomu a interpretace jejich variability. Při hledání genetické příčiny vzácných nemocí je třeba cíleně analyzovat biologické tekutiny, tkáně i vhodné buněčné a zvířecí modely připravované metodami buněčného reprogramování nebo cílených změn genomu. Přinášíme stručný přehled metod, které zahrnují celoexomové a celogenomové sekvenování nové generace, funkční a homologní klonování, funkční komplementaci, mapování genů pomocí vazebné analýzy a porovnávání genomové informace jedince nebo skupiny jedinců s genetickou variabilitou populace. Exomovou analýzu jsme provedli u více než 520 pacientů s diagnostickou úspěšnosti nad 50 %. Srovnáním vlastních výsledků celoexomového sekvenování s výsledky cíleného sekvenování jsme v souboru 225 nemocných došli k závěru, že diagnosticky i ekonomicky je smysluplnější indikovat celoexomové a v blízké budoucnosti celogenomové sekvenování. Moderně koncipovaná diagnostika a výzkum vzácných nemocí je časově, personálně i finančně náročná a vyžaduje spolupráci lékařů s pracovišti biologicky orientovaného výzkumu. Jejich nezbytnost pro české zdravotnictví představuje výzvu pro organizátory i plátce českého zdravotnictví a výzkumu. Klíčová slova: vzácná a komplexní onemocnění, celoexomové sekvenování, mapování genů

Rare diseases represent a heterogeneous group of approximately 8000 various disorders and affect nearly 8 % of the population. The local and international studies of human genomes help to increase the knowledge about genetic variability of the man and due to effective sharing of clinical and molecular data in the registries enable casual diagnostics of the broad spectrum of rare and complex diseases in 55–65 % of the cases. With the diagnostics in the remaining group of patients, new methods and technologies studying human genome are of importance including genetic and functional analyses of genomic variants and their combinations with the aims to recognize and interpret the significances of the somatic mosaics, genetic heterogeneity of individual disorders, the presence of eventual phenocopy, different penetrance and expressivity of individual mutation and diseases with the oligogenic inheritance. Recently, the increasing significance of analyses of noncoding regions in human DNA were recognized including the impact of repetitive and homologs regions on transcription and structure of mRNA. For the diagnostics of genetic causality in patients is necessary to focus on analyses of biologic fluids, tissues, cultivated cells and animal models prepared by methods of cell reprogramming or directed mutagenesis. In this paper, the overview of methods and their importance and limitation is described including whole exome sequencing (WES), whole genome sequencing, functional and homolog cloning, functional complementation, mapping of genes with the help of binding analyses and matching of the results from individual genome with genetic variability in the adequate population. In our institutions, we performed WES in > 520 patients with successful diagnostics above 50 %. In addition, in our group of 225 patients with rare diseases we compared the result of WES with the results of direct sequencing of individual genes indicated by clinical geneticist from various regions of the country and we recognized much higher diagnostic and economic value of WES. Modern diagnostics of rare diseases is time and money consuming and requires close cooperation between patients, their families, attending physicians, clinical geneticists and experts from various laboratories involved in biologic oriented research. It represents a big challenge for organisers and payers of the health care system. Keywords: are diseases, complex disorders, whole exome sequencing, gene mapping

• MeSH
• lidé MeSH
• mapování chromozomů metody   MeSH
• mutace genetika   MeSH
• sekvenování exomu * metody   MeSH
• vzácné nemoci * diagnóza   genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

The formation of the vertebrate brain requires the generation, migration, differentiation and survival of neurons. Genetic mutations that perturb these critical cellular events can result in malformations of the telencephalon, providing a molecular window into brain development. Here we report the identification of an N-ethyl-N-nitrosourea-induced mouse mutant characterized by a fractured hippocampal pyramidal cell layer, attributable to defects in neuronal migration. We show that this is caused by a hypomorphic mutation in Vps15 that perturbs endosomal-lysosomal trafficking and autophagy, resulting in an upregulation of Nischarin, which inhibits Pak1 signaling. The complete ablation of Vps15 results in the accumulation of autophagic substrates, the induction of apoptosis and severe cortical atrophy. Finally, we report that mutations in VPS15 are associated with cortical atrophy and epilepsy in humans. These data highlight the importance of the Vps15-Vps34 complex and the Nischarin-Pak1 signaling hub in the development of the telencephalon.

• MeSH
• alkylační látky toxicita   MeSH
• atrofie chemicky indukované   genetika   patologie   MeSH
• autofagie účinky léků   genetika   MeSH
• embryo savčí MeSH
• ethylnitrosomočovina toxicita   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• mozek účinky léků   patologie   MeSH
• mutace účinky léků   MeSH
• myši inbrední C57BL MeSH
• myši transgenní MeSH
• myši MeSH
• neurony účinky léků   patologie   ultrastruktura   MeSH
• neurovývojové poruchy * chemicky indukované   diagnostické zobrazování   genetika   patologie   MeSH
• novorozená zvířata MeSH
• pohyb buněk účinky léků   genetika   MeSH
• signální transdukce účinky léků   genetika   MeSH
• vakuolární protonové ATPasy účinky léků   genetika   MeSH
• vývojová regulace genové exprese účinky léků   genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In a large family of Czech origin, we mapped a locus for an autosomal-dominant corneal endothelial dystrophy, posterior polymorphous corneal dystrophy 4 (PPCD4), to 8q22.3-q24.12. Whole-genome sequencing identified a unique variant (c.20+544G>T) in this locus, within an intronic regulatory region of GRHL2. Targeted sequencing identified the same variant in three additional previously unsolved PPCD-affected families, including a de novo occurrence that suggests this is a recurrent mutation. Two further unique variants were identified in intron 1 of GRHL2 (c.20+257delT and c.20+133delA) in unrelated PPCD-affected families. GRHL2 is a transcription factor that suppresses epithelial-to-mesenchymal transition (EMT) and is a direct transcriptional repressor of ZEB1. ZEB1 mutations leading to haploinsufficiency cause PPCD3. We previously identified promoter mutations in OVOL2, a gene not normally expressed in the corneal endothelium, as the cause of PPCD1. OVOL2 drives mesenchymal-to-epithelial transition (MET) by directly inhibiting EMT-inducing transcription factors, such as ZEB1. Here, we demonstrate that the GRHL2 regulatory variants identified in PPCD4-affected individuals induce increased transcriptional activity in vitro. Furthermore, although GRHL2 is not expressed in corneal endothelial cells in control tissue, we detected GRHL2 in the corneal "endothelium" in PPCD4 tissue. These cells were also positive for epithelial markers E-Cadherin and Cytokeratin 7, indicating they have transitioned to an epithelial-like cell type. We suggest that mutations inducing MET within the corneal endothelium are a convergent pathogenic mechanism leading to dysfunction of the endothelial barrier and disease.

• MeSH
• dědičné dystrofie rohovky genetika   MeSH
• DNA vazebné proteiny genetika   MeSH
• genetická transkripce MeSH
• genetické lokusy MeSH
• HEK293 buňky MeSH
• intergenová DNA genetika   MeSH
• introny genetika   MeSH
• lidé MeSH
• modely genetické MeSH
• mutace genetika   MeSH
• promotorové oblasti (genetika) genetika   MeSH
• rodina MeSH
• rodokmen MeSH
• rohovkový endotel patologie   MeSH
• sekvence nukleotidů MeSH
• sekvenování celého genomu MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cardiomyopathy is a common manifestation in neonates and infants with mitochondrial disorders. In this study, we report two cases manifesting with fatal mitochondrial hypertrophic cardiomyopathy, which include the third known patient with thymidine kinase 2 deficiency and the ninth patient with alanyl-tRNA synthetase 2 deficiency. The girl with thymidine kinase 2 deficiency had hypertrophic cardiomyopathy together with regression of gross motor development at the age of 13 months. Neurological symptoms and cardiac involvement progressed into severe myopathy, psychomotor arrest, and cardiorespiratory failure at the age of 22 months. The imaging methods and autoptic studies proved that she suffered from unique findings of leucoencephalopathy, severe, mainly cerebellar neuronal degeneration, and hepatic steatosis. The girl with alanyl-tRNA synthetase 2 deficiency presented with cardiac failure and underlying hypertrophic cardiomyopathy within 12 hours of life and subsequently died at 9 weeks of age. Muscle biopsy analyses demonstrated respiratory chain complex I and IV deficiencies, and histological evaluation revealed massive mitochondrial accumulation and cytochrome c oxidase-negative fibres in both cases. Exome sequencing in the first case revealed compound heterozygozity for one novel c.209T>C and one previously published c.416C>T mutation in the TK2 gene, whereas in the second case homozygozity for the previously described mutation c.1774C>T in the AARS2 gene was determined. The thymidine kinase 2 mutations resulted in severe mitochondrial DNA depletion (to 12% of controls) in the muscle. We present, for the first time, severe leucoencephalopathy and hepatic steatosis in a patient with thymidine kinase 2 deficiency and the finding of a ragged red fibre-like image in the muscle biopsy in a patient with alanyl-tRNA synthetase 2 deficiency.

• MeSH
• alanin-tRNA-ligasa nedostatek   genetika   MeSH
• bílá hmota diagnostické zobrazování   MeSH
• echokardiografie MeSH
• fatální výsledek MeSH
• hypertrofická kardiomyopatie diagnostické zobrazování   genetika   MeSH
• kojenec MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mitochondriální DNA genetika   MeSH
• mitochondriální nemoci genetika   MeSH
• mutace MeSH
• novorozenec MeSH
• pitva MeSH
• thymidinkináza nedostatek   genetika   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• přehledy MeSH

A bilaterally blind woman, with a three generation family history of autosomal dominant congenital cataracts, variably associated with iris colobomata and microcornea, sought preconception genetic consultation. Whole-exome sequencing was performed in three affected family members, one unaffected first degree relative, and one spouse. The sequence variant c.168C>G; p.(Tyr56∗) in CRYGD, previously reported as pathogenic, and a novel mutation c.809C>A; p.(Ser270Tyr) in MAF, were identified in two affected family members; the grandmother, and half-brother of the proband. The proband inherited only the MAF mutation, whereas her clinically unaffected sister had the CRYGD change. In silico analysis supported a pathogenic role of p.(Ser270Tyr) in MAF, which was absent from publicly available whole-exome datasets, and 1161 Czech individuals. The frequency of CRYGD p.(Tyr56∗) in the ExAC dataset was higher than the estimated incidence of congenital cataract in the general population. Our study highlights that patients with genetically heterogeneous conditions may exhibit rare variants in more than one disease-associated gene, warranting caution with data interpretation, and supporting parallel screening of all genes known to harbour pathogenic mutations for a given phenotype. The pathogenicity of sequence variants previously reported as cataract-causing may require re-assessment in light of recently released datasets of human genomic variation.

• MeSH
• dominantní geny genetika   MeSH
• dospělí MeSH
• exom genetika   MeSH
• fenotyp MeSH
• gama-krystaliny genetika   metabolismus   MeSH
• katarakta vrozené   genetika   MeSH
• lidé MeSH
• mutace genetika   MeSH
• mutační analýza DNA metody   MeSH
• protoonkogenní proteiny c-maf genetika   metabolismus   MeSH
• rodokmen MeSH
• sekvenování exomu metody   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Congenital hereditary endothelial dystrophy 1 (CHED1) and posterior polymorphous corneal dystrophy 1 (PPCD1) are autosomal-dominant corneal endothelial dystrophies that have been genetically mapped to overlapping loci on the short arm of chromosome 20. We combined genetic and genomic approaches to identify the cause of disease in extensive pedigrees comprising over 100 affected individuals. After exclusion of pathogenic coding, splice-site, and copy-number variations, a parallel approach using targeted and whole-genome sequencing facilitated the identification of pathogenic variants in a conserved region of the OVOL2 proximal promoter sequence in the index families (c.-339_361dup for CHED1 and c.-370T>C for PPCD1). Direct sequencing of the OVOL2 promoter in other unrelated affected individuals identified two additional mutations within the conserved proximal promoter sequence (c.-274T>G and c.-307T>C). OVOL2 encodes ovo-like zinc finger 2, a C2H2 zinc-finger transcription factor that regulates mesenchymal-to-epithelial transition and acts as a direct transcriptional repressor of the established PPCD-associated gene ZEB1. Interestingly, we did not detect OVOL2 expression in the normal corneal endothelium. Our in vitro data demonstrate that all four mutated OVOL2 promoters exhibited more transcriptional activity than the corresponding wild-type promoter, and we postulate that the mutations identified create cryptic cis-acting regulatory sequence binding sites that drive aberrant OVOL2 expression during endothelial cell development. Our data establish CHED1 and PPCD1 as allelic conditions and show that CHED1 represents the extreme of what can be considered a disease spectrum. They also implicate transcriptional dysregulation of OVOL2 as a common cause of dominantly inherited corneal endothelial dystrophies.

• MeSH
• alely * MeSH
• dědičné dystrofie rohovky genetika   MeSH
• DNA MeSH
• lidé MeSH
• mutace * MeSH
• promotorové oblasti (genetika) * MeSH
• rodokmen MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie nukleových kyselin MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Background: Mutations in the RMND1 (Required for Meiotic Nuclear Division protein 1) gene have recently been linked to infantile onset mitochondrial disease characterised by multiple mitochondrial respiratory chain defects. Methods: We summarised the clinical, biochemical and molecular genetic investigation of an international cohort of affected individuals with RMND1 mutations. In addition, we reviewed all the previously published cases to determine the genotype-phenotype correlates and performed survival analysis to identify prognostic factors. Results: We identified 14 new cases from 11 pedigrees that harbour recessive RMND1 mutations, including 6 novel variants: c.533C>A, p.(Thr178Lys); c.565C>T, p.(Gln189*); c.631G>A, p.(Val211Met); c.1303C>T, p.(Leu435Phe); c.830+1G>A and c.1317+1G>T. Together with all previously published cases (n=32), we show that congenital sensorineural deafness, hypotonia, developmental delay and lactic acidaemia are common clinical manifestations with disease onset under 2 years. Renal involvement is more prevalent than seizures (66% vs 44%). In addition, median survival time was longer in patients with renal involvement compared with those without renal disease (6 years vs 8 months, p=0.009). The neurological phenotype also appears milder in patients with renal involvement. Conclusions: The clinical phenotypes and prognosis associated with RMND1 mutations are more heterogeneous than that were initially described. Regular monitoring of kidney function is imperative in the clinical practice in light of nephropathy being present in over 60% of cases. Furthermore, renal replacement therapy should be considered particularly in those patients with mild neurological manifestation as shown in our study that four recipients of kidney transplant demonstrate good clinical outcome to date.

• Klíčová slova
• RMND1,
• MeSH
• dítě MeSH
• genetické asociační studie MeSH
• lidé MeSH
• mitochondriální nemoci * genetika   MeSH
• mutace genetika   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• klinická studie MeSH
• práce podpořená grantem MeSH

OBJECTIVE: To critically re-evaluate cases diagnosed as adult neuronal ceroid lipofuscinosis (ANCL) in order to aid clinicopathologic diagnosis as a route to further gene discovery. METHODS: Through establishment of an international consortium we pooled 47 unsolved cases regarded by referring centers as ANCL. Clinical and neuropathologic experts within the Consortium established diagnostic criteria for ANCL based on the literature to assess each case. A panel of 3 neuropathologists independently reviewed source pathologic data. Cases were given a final clinicopathologic classification of definite ANCL, probable ANCL, possible ANCL, or not ANCL. RESULTS: Of the 47 cases, only 16 fulfilled the Consortium's criteria of ANCL (5 definite, 2 probable, 9 possible). Definitive alternate diagnoses were made in 10, including Huntington disease, early-onset Alzheimer disease, Niemann-Pick disease, neuroserpinopathy, prion disease, and neurodegeneration with brain iron accumulation. Six cases had features suggesting an alternate diagnosis, but no specific condition was identified; in 15, the data were inadequate for classification. Misinterpretation of normal lipofuscin as abnormal storage material was the commonest cause of misdiagnosis. CONCLUSIONS: Diagnosis of ANCL remains challenging; expert pathologic analysis and recent molecular genetic advances revealed misdiagnoses in >1/3 of cases. We now have a refined group of cases that will facilitate identification of new causative genes.

• MeSH
• chybná diagnóza * MeSH
• dospělí MeSH
• lidé MeSH
• lipofuscin metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• neuronální ceroidlipofuscinózy klasifikace   diagnóza   genetika   metabolismus   MeSH
• neurony metabolismus   ultrastruktura   MeSH
• věk při počátku nemoci MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• Publikační typ
• časopisecké články MeSH