The aim of this study was to identify the molecular genetic cause of disease in posterior polymorphous corneal dystrophy (PPCD) probands of diverse origin and to assess the utility of massively parallel sequencing in the detection of ZEB1 mutations. We investigated a total of 12 families (five British, four Czech, one Slovak and two Swiss). Ten novel and two recurrent disease-causing mutations in ZEB1, were identified in probands by Sanger (n = 5), exome (n = 4) and genome (n = 3) sequencing. Sanger sequencing was used to confirm the mutations detected by massively parallel sequencing, and to perform segregation analysis. Genome sequencing revealed that one proband harboured a novel ∼0.34 Mb heterozygous de novo deletion spanning exons 1-7 and part of exon 8. Transcript analysis confirmed that the ZEB1 transcript is detectable in blood-derived RNA samples and that the disease-associated variant c.482-2A>G leads to aberrant pre-mRNA splicing. De novo mutations, which are a feature of PPCD3, were found in the current study with an incidence rate of at least 16.6%. In general, massively parallel sequencing is a time-efficient way to detect PPCD3-associated mutations and, importantly, genome sequencing enables the identification of full or partial heterozygous ZEB1 deletions that can evade detection by both Sanger and exome sequencing. These findings contribute to our understanding of PPCD3, for which currently, 49 pathogenic variants have been identified, all of which are predicted to be null alleles.

• MeSH
• dědičné dystrofie rohovky diagnóza   genetika   metabolismus   MeSH
• dítě MeSH
• DNA genetika   MeSH
• dospělí MeSH
• exony MeSH
• heterozygot MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• předškolní dítě MeSH
• rodokmen MeSH
• sekvence nukleotidů MeSH
• sekvenční delece MeSH
• senioři MeSH
• transkripční faktor Zeb1 genetika   metabolismus   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zinkové prsty MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• předškolní dítě MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Although genetic lesions responsible for some mendelian disorders can be rapidly discovered through massively parallel sequencing of whole genomes or exomes, not all diseases readily yield to such efforts. We describe the illustrative case of the simple mendelian disorder medullary cystic kidney disease type 1 (MCKD1), mapped more than a decade ago to a 2-Mb region on chromosome 1. Ultimately, only by cloning, capillary sequencing and de novo assembly did we find that each of six families with MCKD1 harbors an equivalent but apparently independently arising mutation in sequence markedly under-represented in massively parallel sequencing data: the insertion of a single cytosine in one copy (but a different copy in each family) of the repeat unit comprising the extremely long (~1.5-5 kb), GC-rich (>80%) coding variable-number tandem repeat (VNTR) sequence in the MUC1 gene encoding mucin 1. These results provide a cautionary tale about the challenges in identifying the genes responsible for mendelian, let alone more complex, disorders through massively parallel sequencing.

• MeSH
• cytosin metabolismus   MeSH
• genetická vazba MeSH
• haplotypy MeSH
• lidé MeSH
• minisatelitní repetice * genetika   MeSH
• mucin 1 * genetika   metabolismus   MeSH
• mutace * MeSH
• polycystické ledviny autozomálně dominantní * MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

The information on candidate cancer driver alterations available from public databases is often descriptive and of limited mechanistic insight, which poses difficulties for reliable distinction between true driver and passenger events. To address this challenge, we performed in-depth analysis of whole-exome sequencing data from cell lines generated by a barrier bypass-clonal expansion (BBCE) protocol. The employed strategy is based on carcinogen-driven immortalization of primary mouse embryonic fibroblasts and recapitulates early steps of cell transformation. Among the mutated genes were almost 200 COSMIC Cancer Gene Census genes, many of which were recurrently affected in the set of 25 immortalized cell lines. The alterations affected pathways regulating DNA damage response and repair, transcription and chromatin structure, cell cycle and cell death, as well as developmental pathways. The functional impact of the mutations was strongly supported by the manifestation of several known cancer hotspot mutations among the identified alterations. We identified a new set of genes encoding subunits of the BAF chromatin remodeling complex that exhibited Ras-mediated dependence on PRC2 histone methyltransferase activity, a finding that is similar to what has been observed for other BAF subunits in cancer cells. Among the affected BAF complex subunits, we determined Smarcd2 and Smarcc1 as putative driver candidates not yet fully identified by large-scale cancer genome sequencing projects. In addition, Ep400 displayed characteristics of a driver gene in that it showed a mutually exclusive mutation pattern when compared with mutations in the Trrap subunit of the TIP60 complex, both in the cell line panel and in a human tumor data set. We propose that the information generated by deep sequencing of the BBCE cell lines coupled with phenotypic analysis of the mutant cells can yield mechanistic insights into driver events relevant to human cancer development.

• MeSH
• exom genetika   MeSH
• fibroblasty MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorová transformace buněk genetika   MeSH
• nádorové proteiny genetika   MeSH
• nádory genetika   MeSH
• primární buněčná kultura MeSH
• vysoce účinné nukleotidové sekvenování * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

• MeSH
• intersticiální nefritida * diagnóza   genetika   MeSH
• lidé MeSH
• mucin 1 * genetika   MeSH
• mutace MeSH
• nemoci ledvin genetika   MeSH
• rodokmen MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• dopisy MeSH
• práce podpořená grantem MeSH

Metagenomic high-throughput sequencing (mHTS) is a hypothesis-free, universal pathogen detection technique for determination of the DNA/RNA sequences in a variety of sample types and infectious syndromes. mHTS is still in its early stages of translating into clinical application. To support the development, implementation and standardization of mHTS procedures for virus diagnostics, the European Society for Clinical Virology (ESCV) Network on Next-Generation Sequencing (ENNGS) has been established. The aim of ENNGS is to bring together professionals involved in mHTS for viral diagnostics to share methodologies and experiences, and to develop application recommendations. This manuscript aims to provide practical recommendations for the wet lab procedures necessary for implementation of mHTS for virus diagnostics and to give recommendations for development and validation of laboratory methods, including mHTS quality assurance, control and quality assessment protocols.

• MeSH
• metagenomika * MeSH
• viry * genetika   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Publikační typ
• časopisecké články MeSH

Sekvenování nové generace, nazývané také masivně paralelní sekvenování (MPS), je v současnosti nejrychleji se rozvíjející metodou molekulární genetiky, která přinese zlom v oblasti personalizované medicíny. V tomto přehledu stručně popisujeme hlavní typy MPS, kterými jsou celogenomová a exomová sekvenace, sekvenace transkriptomu a amplikonové sekvenování. Dále je uveden souhrn výhod, nevýhod a možných aplikací technologií nabízených v současnosti v České republice.

Next generation or massive parallel sequencing (MPS) is a rapidly advancing method in molecular genetics that will bring significant changes in the personalized medicine field. In this review we briefly describe major types of MPS, including whole-genome, -exome, -transcriptome and amplicon sequencing. We also present an overview of the advantages, drawbacks and possible applications of sequencing technologies available in the Czech Republic.

• Klíčová slova
• masivně paralelní sekvenování, amplikonové sekvenování, sekvenování nové generace,
• MeSH
• exom MeSH
• lidé MeSH
• sekvenční analýza DNA * ekonomika   přístrojové vybavení   trendy   MeSH
• sekvenční analýza RNA metody   MeSH
• transkriptom MeSH
• vysoce účinné nukleotidové sekvenování * ekonomika   metody   přístrojové vybavení   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

We describe a patient with early onset severe axonal Charcot-Marie-Tooth disease (CMT2) with dominant inheritance, in whom Sanger sequencing failed to detect a mutation in the mitofusin 2 (MFN2) gene because of a single nucleotide polymorphism (rs2236057) under the PCR primer sequence. The severe early onset phenotype and the family history with severely affected mother (died after delivery) was very suggestive of CMT2A and this suspicion was finally confirmed by a MFN2 mutation. The mutation p.His361Tyr was later detected in the patient by massively parallel sequencing with a gene panel for hereditary neuropathies. According to this information, new primers for amplification and sequencing were designed which bind away from the polymorphic sites of the patient's DNA. Sanger sequencing with these new primers then confirmed the heterozygous mutation in the MFN2 gene in this patient. This case report shows that massively parallel sequencing may in some rare cases be more sensitive than Sanger sequencing and highlights the importance of accurate primer design which requires special attention.

• MeSH
• Charcotova-Marieova-Toothova nemoc diagnóza   genetika   MeSH
• DNA primery MeSH
• GTP-fosfohydrolasy genetika   MeSH
• jednonukleotidový polymorfismus * MeSH
• lidé MeSH
• mitochondriální proteiny genetika   MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• předškolní dítě MeSH
• rodokmen MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH

Patients below 55 years were genetically studied because the prevalence of isocitrate dehydrogenase 1 (IDH1) decreases in older patients and on grounds of cost-effectiveness, as suggested by the World Health Organization (WHO) in 2016. The aim of our study was to use novel massively parallel sequencing (MPS) approaches to examine rare variants of IDH1/2 in Czech diffuse astrocytic and oligodendroglial tumors (gliomas) patients below 55 years of age who had been immunohistochemically (IHC) diagnosed as IDH1 R132H negative. The IHC IDH1 status (wild type or mutant) of 275 tissue samples was analyzed using antibodies against the IDH1 R132H protein. Sixty-three samples of 55 years old patients with IHC IDH1 WT status were genotyped using two different MPS technologies to detect rare IDH1 and IDH2 variants. The tiered IHC (60 positive) and molecular (10 positive) approach thus revealed that 70 of the 275 samples (25%) bore IDH1/IDH2 mutations. The combined molecular and IHC approach thus revealed that 70 of the 275 samples (25%) considered in the study bore IDH1/IDH2 mutations. IHC detection of the IDH1 R132H variant should be routinely complemented with MPS to detect rare IDH1/2 variants in glioma patients below 55 years of age with negative IHC result of IDH R132H variant.

• MeSH
• gliom * patologie   MeSH
• isocitrátdehydrogenasa genetika   metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace MeSH
• nádory mozku * diagnóza   MeSH
• retrospektivní studie MeSH
• senioři MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Circulating tumor DNA (ctDNA) sequencing is being rapidly adopted in precision oncology, but the accuracy, sensitivity and reproducibility of ctDNA assays is poorly understood. Here we report the findings of a multi-site, cross-platform evaluation of the analytical performance of five industry-leading ctDNA assays. We evaluated each stage of the ctDNA sequencing workflow with simulations, synthetic DNA spike-in experiments and proficiency testing on standardized, cell-line-derived reference samples. Above 0.5% variant allele frequency, ctDNA mutations were detected with high sensitivity, precision and reproducibility by all five assays, whereas, below this limit, detection became unreliable and varied widely between assays, especially when input material was limited. Missed mutations (false negatives) were more common than erroneous candidates (false positives), indicating that the reliable sampling of rare ctDNA fragments is the key challenge for ctDNA assays. This comprehensive evaluation of the analytical performance of ctDNA assays serves to inform best practice guidelines and provides a resource for precision oncology.

• MeSH
• cirkulující nádorová DNA genetika   MeSH
• individualizovaná medicína * MeSH
• lékařská onkologie * MeSH
• lidé MeSH
• limita detekce MeSH
• nádory genetika   MeSH
• reprodukovatelnost výsledků MeSH
• sekvenční analýza DNA normy   MeSH
• směrnice pro lékařskou praxi jako téma MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, N.I.H., Intramural MeSH
• validační studie MeSH

Východiska: Karcinom ovaria, závažné nádorové onemocnění s vysokou mortalitou, je v České republice diagnostikováno každým rokem přibližně u 1 000 žen. Riziko vzniku onemocnění je zvýšeno u nosiček mutací v některých nádorových predispozičních genech. S vysokým relativním rizikem (RR > 5) jsou spojeny mutace v genech BRCA1, BRCA2, BRIP1, geny Lynchova syndromu, RAD51C, RAD51D, STK11; s možným zvýšením rizika mutace v genech ATM, CHEK2, NBN, PALB2, BARD1. Cílem práce bylo určit frekvenci mutací v nádorových predispozičních genech v naší populaci. Metody a výsledky: Celkem 1 057 pacientek s karcinomem ovaria a 617 nenádorových kontrol bylo vyšetřeno pomocí panelového sekvenování nové generace na platformě Illumina. Patogenní mutace ve vysoko rizikových genech, vč. velkých genomových přestaveb, byly v našem souboru zachyceny u 30,6 % pacientek; u neselektovaných pacientek byla frekvence mutací téměř 25 %, u pacientek s negativní rodinnou anamnézou 18 %. Nejčastěji mutovanými predispozičními geny byly BRCA1 a BRCA2, součet frekvence mutací v ostatních ovariálních predispozičních genech odpovídal frekvenci mutací v genu BRCA2. Záchyt mutací u pacientek starších 70 let byl více než třikrát vyšší v porovnání s pacientkami ve věku pod 30 let. Závěr: Karcinom ovaria je heterogenní onemocnění s vysokým podílem dědičné formy onemocnění. Vzhledem k nedostatku adekvátních screeningových modalit pro včasnou diagnostiku onemocnění je identifikace nosiček mutací v ovariálních predispozičních genech klíčová, s vysokým potenciálem k celkovému snížení mortality z důvodu karcinomu ovaria.

Background: Ovarian cancer is a disease with high mortality. Approximately 1,000 women are diagnosed with ovarian cancer in the Czech Republic annually. Women harboring a mutation in cancer-predisposing genes face an increased risk of tumor development. Mutations in BRCA1, BRCA2, BRIP1, and Lynch syndrome genes (RAD51C, RAD51D, and STK11) are associated with a high risk of ovarian cancer, and mutations in ATM, CHEK2, NBN, PALB2, and BARD1 appear to increase the risk. Our aim was to examine the frequency of mutations in cancer-predisposing genes in the Czech Republic. Materials and methods: We analyzed 1,057 individuals including ovarian cancer patients and 617 non-cancer controls using CZECANCA panel next-generation sequencing on the Illumina platform. Pathogenic mutations in high-risk genes, including CNVs, were detected in 30.6% of patients. The mutation frequency reached 25.0% and 18.2% in subgroups of unselected ovarian cancer patients and patients with a negative family cancer history, respectively. The most frequently mutated genes were BRCA1 and BRCA2. The overall frequency of mutations in non-BRCA genes was comparable to that in BRCA2. The mutation frequency in ovarian cancer patients aged > 70 years was three times higher than that in patients diagnosed before the age of 30. Conclusion: Ovarian cancer is a heterogeneous disease with a high proportion of hereditary cases. The lack of efficient screening for early diagnosis emphasizes the importance of identifying carriers of mutations in ovarian cancer-predisposing genes; this is because proper follow-up and prevention strategies can reduce overall ovarian cancer-related mortality.

• Klíčová slova
• panel genů,
• MeSH
• geny nádorové MeSH
• klinická studie jako téma MeSH
• lidé MeSH
• mutace MeSH
• nádory vaječníků * genetika   MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH