Deficit transportu riboflavinu (RTD), známý také jako Brown-Vialetto-van Laere syndrom, je vzácné onemocnění, které na základě poruchy oxidativního metabolizmu vede k úbytku neuronů v jádrech hlavových i periferních nervů. Projevy jsou ztráta svalové síly, ptóza očního víčka, bulbární syndrom a respirační potíže doprovázené těžkou postsynaptickou sluchovou neuropatií. Je-li projeven v dětském věku, vede k úmrtí pro respirační selhání v řádu měsíců až let. Na prezentovaném případu familiárního výskytu u sourozenců je demonstrována nutnost rychlého zahájení substituční léčby riboflavinem, která může předejít rozvoji onemocnění nebo alespoň zmírnit jeho projevy a zvýšit šanci na úspěšnou rehabilitaci sluchu. Při záchytu sluchové neuropatie u dětí doporučujeme vyšetření multigenového NGS/MPS panelu, který zahrnuje i vzácnější příčiny vrozené poruchy sluchu. V případě výskytu jakéhokoli dalšího příznaku onemocnění je třeba neprodleně zahájit substituční léčbu.

Riboflavin transporter deficiency (RTD) is rare disease characterized by progressive loss of cranial and somatic nerve function. Typically ptosis, bulbar syndrome, muscle weakness, and auditory neuropathy are manifested. Without treatment, this leads to death caused by respiratory failure, especially when it starts in childhood. In this paper, we present two siblings with RTD and demonstrate the necessity of early diagnosis and riboflavin substitution treatment. Riboflavin substitution can prevent hearing loss and increase the chance for successful hearing rehabilitation. Comparison with other existing literature is given. We recommend to test every child with captured auditory neuropathy spectrum disorder for a multi-gene NGS/MPS panel and provide substitution treatment before genetic test results, especially when other symptoms are manifested.

• MeSH
• Child MeSH
• Genetic Testing MeSH
• Cochlear Implants MeSH
• Infant MeSH
• Humans MeSH
• Riboflavin Deficiency * diagnosis   genetics   therapy   MeSH
• Hearing Disorders etiology   therapy   MeSH
• Riboflavin therapeutic use   MeSH
• Family MeSH
• Check Tag
• Child MeSH
• Infant MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Case Reports MeSH
• Review MeSH

Endometrial cancer (EC) is the most common gynecological malignancy in developed countries. The present study aimed to determine the frequency of germline pathogenic variants (PV) in patients with EC. In this multicenter retrospective cohort study, germline genetic testing (GGT) was performed in 527 patients with EC using a next generation sequencing panel targeting 226 genes, including 5 Lynch syndrome (LS) and 14 hereditary breast and ovarian cancer (HBOC) predisposition genes, and 207 candidate predisposition genes. Gene-level risks were calculated using 1,662 population-matched controls (PMCs). Patients were sub-categorized to fulfill GGT criteria for LS, HBOC, both or none. A total of 60 patients (11.4%) carried PV in LS (5.1%) and HBOC (6.6%) predisposition genes, including two carriers of double PV. PV in LS genes conferred a significantly higher EC risk [odds ratio (OR), 22.4; 95% CI, 7.8-64.3; P=1.8×10-17] than the most frequently altered HBOC genes BRCA1 (OR, 3.9; 95% CI, 1.6-9.5; P=0.001), BRCA2 (OR, 7.4; 95% CI, 1.9-28.9; P=0.002) and CHEK2 (OR, 3.2; 95% CI, 1.0-9.9; P=0.04). Furthermore, >6% of patients with EC not fulfilling LS or HBOC GGT indication criteria carried a PV in a clinically relevant gene. Carriers of PV in LS genes had a significantly lower age of EC onset than non-carriers (P=0.01). Another 11.0% of patients carried PV in a candidate gene (the most frequent were FANCA and MUTYH); however, their individual frequencies did not differ from PMCs (except for aggregated frequency of loss-of-function variants in POLE/POLD1; OR, 10.44; 95% CI, 1.1-100.5; P=0.012). The present study demonstrated the importance of GGT in patients with EC. The increased risk of EC of PV carriers in HBOC genes suggests that the diagnosis of EC should be included in the HBOC GGT criteria.

• Publication type
• Journal Article MeSH

Hypertrofická kardiomyopatie (HKMP) je s předpokládanou prevalencí 1/500 až 1/200 obyvatel jedním z nejčastějších geneticky podmíněných srdečních onemocnění. Pro HKMP je charakteristická výrazná fenotypová i genotypová heterogenita. Pacienti s HKMP by měli být komplexně a mutidisciplinárně vyšetřeni, aby nebyly přehlédnuty některé syndromické formy s možností individualizované terapie. Při molekulárně genetickém vyšetření současnými metodami včetně sekvenování nové generace (NGS) u velké části pacientů nezachytíme žádnou patogenní nebo pravděpodobně patogenní (P/LP) variantu. Bez ohledu na použitou metodu by měla molekulárně genetická analýza vždy zahrnovat nejčastější sarkomerické geny. Dostupnými metodami NGS přichází možnost vyšetření velkého množství genů, včetně celoexomového (WES) a celogenomového (WGS) vyšetření. Větší objem dat obvykle nezvyšuje pravděpodobnost záchytu P/LP mutací a vede k nárůstu nálezů variant nejasného významu (VUS), jejichž klinická relevance je diskutabilní. Kaskádový rodinný screening je zásadní. Molekulárně genetické vyšetření je vhodné především tam, kde příbuzní mají zájem o přesnější určení rizika onemocnění a jejich následnou dispenzarizaci. Potvrzení přítomnosti P/LP mutace však nutně nemusí znamenat rozvoj HKMP. Komplexní přístup k pacientům s hypertrofickou kardiomyopatií vyžaduje úzkou mezioborovou spolupráci kardiologa, molekulárního genetika, klinického genetika, dětského kardiologa i jiných specializací. Nezbytnou podmínkou genetického vyšetření a využití jeho výstupů v praxi je sledování v expertních centrech se zkušenostmi s molekulárně genetickým vyšetřováním a jeho klinickou interpretací. © 2020, ČKS.

Hypertrophic cardiomyopathy (HCM) is one of the most frequent inherited cardiac disorders with an estimated prevalence of 1 in 500 up to 1 in 200 individuals. The phenotypic heterogeneity of HCM corresponds with the marked heterogeneity in the underlying genotype. Multidisciplinary approach to HCM patients is needed and includes the collaboration of cardiologists with molecular genetics, clinical genetics, paediatric cardiologists and other specialists. Advances in contemporary DNA-sequencing methodology make gene-based diagnosis increasingly feasible in routine clinical practice. It allows rapid analysis of large multigene testing panels (e.g. cardiovascular gene panels, whole-exome sequencing [WES], and whole-genome sequencing [WGS]). Screening of large number of genes does not necessarily result in an identification of pathogenic/likely pathogenic DNA variants (P/LP) and many genetic variants of uncertain significance (VUS) are identified. Genetic testing may lead to individualized therapy in some cases, but is mainly a useful tool for family cascade screening and assessing their risk for HCM. Nevertheless, documentation of P/LP variant in a relative does not necessarily lead to development of overt clinical disease due to variable penetrance and expressivity of DNA variants. The complex interpretation of multidisciplinary findings, genetic results, and family cascade screening belongs to tertiary referral centres with corresponding experience and availability of all subspecialties.

• Keywords
• kaskádový screening,
• MeSH
• Genetic Testing * classification   MeSH
• Cardiomyopathy, Hypertrophic * diagnosis   genetics   complications   MeSH
• Humans MeSH
• Check Tag
• Humans MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH

Ovarian cancer (OC) is the deadliest gynecologic malignancy with a substantial proportion of hereditary cases and a frequent association with breast cancer (BC). Genetic testing facilitates treatment and preventive strategies reducing OC mortality in mutation carriers. However, the prevalence of germline mutations varies among populations and many rarely mutated OC predisposition genes remain to be identified. We aimed to analyze 219 genes in 1333 Czech OC patients and 2278 population-matched controls using next-generation sequencing. We revealed germline mutations in 18 OC/BC predisposition genes in 32.0% of patients and in 2.5% of controls. Mutations in BRCA1/BRCA2, RAD51C/RAD51D, BARD1, and mismatch repair genes conferred high OC risk (OR > 5). Mutations in BRIP1 and NBN were associated with moderate risk (both OR = 3.5). BRCA1/2 mutations dominated in almost all clinicopathological subgroups including sporadic borderline tumors of ovary (BTO). Analysis of remaining 201 genes revealed somatic mosaics in PPM1D and germline mutations in SHPRH and NAT1 associating with a high/moderate OC risk significantly; however, further studies are warranted to delineate their contribution to OC development in other populations. Our findings demonstrate the high proportion of patients with hereditary OC in Slavic population justifying genetic testing in all patients with OC, including BTO.

• Publication type
• Journal Article MeSH

Purpose: To describe a snapshot of international genetic testing practices, specifically regarding the use of multigene panels, for hereditary breast/ovarian cancers. We conducted a survey through the Evidence-Based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) consortium, covering questions about 16 non-BRCA1/2 genes. Methods: Data were collected via in-person and paper/electronic surveys. ENIGMA members from around the world were invited to participate. Additional information was collected via country networks in the United Kingdom and in Italy. Results: Responses from 61 cancer genetics practices across 20 countries showed that 16 genes were tested by > 50% of the centers, but only six (PALB2, TP53, PTEN, CHEK2, ATM, and BRIP1) were tested regularly. US centers tested the genes most often, whereas United Kingdom and Italian centers with no direct ENIGMA affiliation at the time of the survey were the least likely to regularly test them. Most centers tested the 16 genes through multigene panels; some centers tested TP53, PTEN, and other cancer syndrome-associated genes individually. Most centers reported (likely) pathogenic variants to patients and would test family members for such variants. Gene-specific guidelines for breast and ovarian cancer risk management were limited and differed among countries, especially with regard to starting age and type of imaging and risk-reducing surgery recommendations. Conclusion: Currently, a small number of genes beyond BRCA1/2 are routinely analyzed worldwide, and management guidelines are limited and largely based on expert opinion. To attain clinical implementation of multigene panel testing through evidence-based management practices, it is paramount that clinicians (and patients) participate in international initiatives that share panel testing data, interpret sequence variants, and collect prospective data to underpin risk estimates and evaluate the outcome of risk intervention strategies.

• Keywords
• ENIGMA,
• MeSH
• Alleles MeSH
• Genetic Predisposition to Disease genetics   MeSH
• Genetic Testing methods   MeSH
• Humans MeSH
• Disease Management MeSH
• Evidence-Based Medicine MeSH
• Breast Neoplasms * genetics   MeSH
• Ovarian Neoplasms * genetics   MeSH
• Surveys and Questionnaires MeSH
• Germ-Line Mutation genetics   MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Clinical Study MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: Primary ciliary dyskinesia (PCD) is a multigenic autosomal recessive condition affecting respiratory tract and other organs where ciliary motility is required. The extent of its genetic heterogeneity is remarkable. The aim of the study was to develop a cost-effective pipeline for genetic diagnostics using a combination of Sanger and next generation sequencing (NGS). MATERIALS AND METHODS: Data and samples of 33 families with 38 affected subjects with PCD diagnosed in childhood were collected over the territory of the Czech Republic. A panel of 18 PCD causative or candidate genes was implemented into an Illumina TruSeq Custom Amplicon NGS assay, and three ancestral mutations in SPAG1 were screened by conventional Sanger sequencing, which was also used for the confirmation of the NGS results and for the analysis of familial segregation. RESULTS: The causative gene was DNAH5 in 11/33 (33%) probands, SPAG1 in 8/33 (24%), and DNAI1, CCDC40, LRRC6 in one family each. If the high proportion of subjects with bi-allelic ancestral mutations in SPAG1 is corroborated in other Caucasian populations, a simple Sanger sequencing test for these three mutations may serve as an effective pre-screening step, being followed by an NGS panel for other, much larger, PCD genes. CONCLUSIONS: We present a combination of Sanger sequencing with an NGS panel for known and candidate PCD genes, implemented in a moderate-size national collection of patients. This strategy has proven to be cost-effective, rapid and reliable, and was able to detect the causative gene in two thirds of our PCD patients.

• MeSH
• Alleles MeSH
• Antigens, Surface genetics   MeSH
• Child MeSH
• Kartagener Syndrome diagnosis   genetics   MeSH
• Infant MeSH
• Humans MeSH
• Adolescent MeSH
• Mutation * MeSH
• Child, Preschool MeSH
• GTP-Binding Proteins genetics   MeSH
• High-Throughput Nucleotide Sequencing * MeSH
• Check Tag
• Child MeSH
• Infant MeSH
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH

BACKGROUND: The anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (moAbs) cetuximab or panitumumab are administered to colorectal cancer (CRC) patients who harbor wild-type RAS proto-oncogenes. However, a percentage of patients do not respond to this treatment. In addition to mutations in the RAS genes, mutations in other genes, such as BRAF, PI3KCA, or PTEN, could be involved in the resistance to anti-EGFR moAb therapy. METHODS: In order to develop a comprehensive approach for the detection of mutations and to eventually identify other genes responsible for resistance to anti-EGFR moAbs, we investigated a panel of 21 genes by parallel sequencing on the Ion Torrent Personal Genome Machine platform. We sequenced 65 CRCs that were treated with cetuximab or panitumumab. Among these, 37 samples were responsive and 28 were resistant. RESULTS: We confirmed that mutations in EGFR-pathway genes (KRAS, NRAS, BRAF, PI3KCA) were relevant for conferring resistance to therapy and could predict response (p = 0.001). After exclusion of KRAS, NRAS, BRAF and PI3KCA combined mutations could still significantly associate to resistant phenotype (p = 0.045, by Fisher exact test). In addition, mutations in FBXW7 and SMAD4 were prevalent in cases that were non-responsive to anti-EGFR moAb. After we combined the mutations of all genes (excluding KRAS), the ability to predict response to therapy improved significantly (p = 0.002, by Fisher exact test). CONCLUSIONS: The combination of mutations at KRAS and at the five gene panel demonstrates the usefulness and feasibility of multigene sequencing to assess response to anti-EGFR moAbs. The application of parallel sequencing technology in clinical practice, in addition to its innate ability to simultaneously examine the genetic status of several cancer genes, proved to be more accurate and sensitive than the presently in use traditional approaches.

• MeSH
• Cetuximab pharmacology   therapeutic use   MeSH
• Adult MeSH
• ErbB Receptors antagonists & inhibitors   MeSH
• Antibodies, Monoclonal, Humanized pharmacology   therapeutic use   MeSH
• Colorectal Neoplasms diagnosis   drug therapy   genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• Antibodies, Monoclonal pharmacology   therapeutic use   MeSH
• Biomarkers, Tumor genetics   MeSH
• Predictive Value of Tests MeSH
• Antineoplastic Agents pharmacology   therapeutic use   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Treatment Outcome MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH