We report on the largest single dataset of patients with PMM2-CDG enrolled in an ongoing international, multicenter natural history study collecting genetic, clinical, and biological information to evaluate similarities with previous studies, report on novel findings, and, additionally, examine potential genotype/phenotype correlations. A total of 137 participants had complete genotype information, representing 60 unique variants, of which the most common were found to be p.Arg141His in 58.4% (n = 80) of participants, followed by p.Pro113Leu (21.2%, n = 29), and p.Phe119Leu (12.4%, n = 17), consistent with previous studies. Interestingly, six new variants were reported, comprised of five missense variants (p.Pro20Leu, p.Tyr64Ser, p.Phe68Cys, p.Tyr76His, and p.Arg238His) and one frameshift (c.696del p.Ala233Argfs∗100). Patient phenotypes were characterized via the Nijmegen Progression CDG Rating Scale (NPCRS), together with biochemical parameters, the most consistently dysregulated of which were coagulation factors, specifically antithrombin (below normal in 79.5%, 93 of 117), in addition to Factor XI and protein C activity. Patient genotypes were classified based upon the predicted pathogenetic mechanism of disease-associated mutations, of which most were found in the catalysis/activation, folding, or dimerization regions of the PMM2 enzyme. Two different approaches were used to uncover genotype/phenotype relationships. The first characterized genotype only by the predicted pathogenic mechanisms and uncovered associated changes in biochemical parameters, not apparent using only NPCRS, involving catalysis/activation, dimerization, folding, and no protein variants. The second approach characterized genotype by the predicted pathogenic mechanism and/or individual variants when paired with a subset of severe nonfunctioning variants and uncovered correlations with both NPCRS and biochemical parameters, demonstrating that p.Cys241Ser was associated with milder disease, while p.Val231Met, dimerization, and folding variants with more severe disease. Although determining comprehensive genotype/phenotype relationships has previously proven challenging for PMM2-CDG, the larger sample size, plus inclusion of biochemical parameters in the current study, has provided new insights into the interplay of genetics with disease. Trial Registration: NCT03173300.

• Klíčová slova
• PMM2, congenital disorders of glycosylation, genetic variations, genotype/phenotype correlations, inherited metabolic disorders, natural history, phosphomannomutase 2-CDG,
• MeSH
• dítě MeSH
• dospělí MeSH
• fenotyp MeSH
• fosfotransferasy (fosfomutasy) * genetika   chemie   MeSH
• genetické asociační studie * MeSH
• genotyp MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace MeSH
• předškolní dítě MeSH
• vrozené poruchy glykosylace * genetika   diagnóza   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH
• Názvy látek
• fosfotransferasy (fosfomutasy) * MeSH
• phosphomannomutase 2, human MeSH Prohlížeč

Corneal dystrophies are a group of predominantly rare inherited disorders. They are by definition bilateral, relatively symmetrical, and without systemic involvement, affecting corneal transparency and/or refraction. Traditional classification of corneal dystrophies is based on slit-lamp appearance, affected corneal layer and histological features. Molecular genetics has provided ultimate proof for the existence of distinct corneal dystrophies and discarded duplicates in their terminology. Currently, there are at least 16 genes with identified pathogenic variants implicated in corneal dystrophies. Herein, we summarise contemporary knowledge on genotype-phenotype correlations of corneal dystrophies, including a critical review of some reported variants, along with the understanding of the underlying pathogenic dystrophic process; essential knowledge for the development of targeted therapies.

• Klíčová slova
• corneal dystrophy, genetics, hereditary, molecular biology,
• MeSH
• dědičné dystrofie rohovky * genetika   terapie   MeSH
• fenotyp MeSH
• genetické asociační studie * MeSH
• genotyp MeSH
• lidé MeSH
• molekulární biologie MeSH
• mutace * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Bardet-Biedl syndrome (BBS) is a recessive genetic disease causing multiple organ anomalies. Most patients carry mutations in genes encoding for the subunits of the BBSome, an octameric ciliary transport complex, or accessory proteins involved in the BBSome assembly or function. BBS proteins have been extensively studied using in vitro, cellular, and animal models. However, the molecular functions of particular BBS proteins and the etiology of the BBS symptoms are still largely elusive. In this study, we applied a meta-analysis approach to study the genotype-phenotype association in humans using our database of all reported BBS patients. The analysis revealed that the identity of the causative gene and the character of the mutation partially predict the clinical outcome of the disease. Besides their potential use for clinical prognosis, our analysis revealed functional differences of particular BBS genes in humans. Core BBSome subunits BBS2, BBS7, and BBS9 manifest as more critical for the function and development of kidneys than peripheral subunits BBS1, BBS4, and BBS8/TTC8, suggesting that incomplete BBSome retains residual function at least in the kidney.

• Klíčová slova
• BBS, BBSome, Bardet-Biedl syndrome, ciliopathy, genotype-phenotype, kidney disease, meta-analysis, rare disease,
• MeSH
• ADP-ribosylační faktory genetika   MeSH
• Bardetův-Biedlův syndrom diagnóza   genetika   MeSH
• fenotyp * MeSH
• genetická predispozice k nemoci * MeSH
• genetické asociační studie * metody   MeSH
• genotyp * MeSH
• kognitivní dysfunkce genetika   MeSH
• ledviny abnormality   MeSH
• lidé MeSH
• mutace MeSH
• nemoci ledvin vrozené   genetika   MeSH
• penetrance MeSH
• proteiny genetika   MeSH
• vrozené vady genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ADP-ribosylační faktory MeSH
• ARL6 protein, human MeSH Prohlížeč
• Bbs2 protein, human MeSH Prohlížeč
• proteiny MeSH

WT1 mutations cause a wide spectrum of renal and extrarenal manifestations. Here we evaluated disease prevalence, phenotype spectrum, and genotype-phenotype correlations of 61 patients with WT1-related steroid-resistant nephrotic syndrome relative to 700 WT1-negative patients, all with steroid-resistant nephrotic syndrome. WT1 patients more frequently presented with chronic kidney disease and hypertension at diagnosis and exhibited more rapid disease progression. Focal segmental glomerulosclerosis was equally prevalent in both cohorts, but diffuse mesangial sclerosis was largely specific for WT1 disease and was present in 34% of cases. Sex reversal and/or urogenital abnormalities (52%), Wilms tumor (38%), and gonadoblastoma (5%) were almost exclusive to WT1 disease. Missense substitutions affecting DNA-binding residues were associated with diffuse mesangial sclerosis (74%), early steroid-resistant nephrotic syndrome onset, and rapid progression to ESRD. Truncating mutations conferred the highest Wilms tumor risk (78%) but typically late-onset steroid-resistant nephrotic syndrome. Intronic (KTS) mutations were most likely to present as isolated steroid-resistant nephrotic syndrome (37%) with a median onset at an age of 4.5 years, focal segmental glomerulosclerosis on biopsy, and slow progression (median ESRD age 13.6 years). Thus, there is a wide range of expressivity, solid genotype-phenotype associations, and a high risk and significance of extrarenal complications in WT1-associated nephropathy. We suggest that all children with steroid-resistant nephrotic syndrome undergo WT1 gene screening.

• MeSH
• časové faktory MeSH
• chronická renální insuficience diagnóza   epidemiologie   genetika   terapie   MeSH
• dítě MeSH
• fenotyp MeSH
• fokálně segmentální glomeruloskleróza diagnóza   epidemiologie   genetika   terapie   MeSH
• genetická predispozice k nemoci MeSH
• genetické asociační studie MeSH
• genetické testování metody   MeSH
• incidence MeSH
• kojenec MeSH
• lidé MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• nefrotický syndrom vrozené   diagnóza   epidemiologie   genetika   terapie   MeSH
• předškolní dítě MeSH
• prevalence MeSH
• prognóza MeSH
• progrese nemoci MeSH
• proteiny WT1 genetika   MeSH
• registrace MeSH
• rizikové faktory MeSH
• věk při počátku nemoci MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteiny WT1 MeSH
• WT1 protein, human MeSH Prohlížeč

PURPOSE: Noonan syndrome (NS) is an autosomal-dominant disorder characterized by craniofacial dysmorphism, growth retardation, cardiac abnormalities, and learning difficulties. It belongs to the RASopathies, which are caused by germ-line mutations in genes encoding components of the RAS mitogen-activated protein kinase (MAPK) pathway. RIT1 was recently reported as a disease gene for NS, but the number of published cases is still limited. METHODS: We sequenced RIT1 in 310 mutation-negative individuals with a suspected RASopathy and prospectively in individuals who underwent genetic testing for NS. Using a standardized form, we recorded clinical features of all RIT1 mutation-positive patients. Clinical and genotype data from 36 individuals with RIT1 mutation reported previously were reviewed. RESULTS: Eleven different RIT1 missense mutations, three of which were novel, were identified in 33 subjects from 28 families; codons 57, 82, and 95 represent mutation hotspots. In relation to NS of other genetic etiologies, prenatal abnormalities, cardiovascular disease, and lymphatic abnormalities were common in individuals with RIT1 mutation, whereas short stature, intellectual problems, pectus anomalies, and ectodermal findings were less frequent. CONCLUSION: RIT1 is one of the major genes for NS. The RIT1-associated phenotype differs gradually from other NS subtypes, with a high prevalence of cardiovascular manifestations, especially hypertrophic cardiomyopathy, and lymphatic problems.Genet Med 18 12, 1226-1234.

• MeSH
• fenotyp MeSH
• genetické asociační studie MeSH
• genotyp MeSH
• hypertrofická kardiomyopatie genetika   patologie   MeSH
• lidé MeSH
• Noonanové syndrom genetika   patologie   MeSH
• Ras proteiny genetika   MeSH
• rodokmen MeSH
• vrozené srdeční vady genetika   patologie   MeSH
• zárodečné mutace MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• Ras proteiny MeSH
• RIT1 protein, human MeSH Prohlížeč

Mucopolysaccharidosis type II (Hunter syndrome, MPS II, OMIM 309900) is an X-linked lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase (IDS). We analyzed clinical and laboratory data from 44 Slavic patients with this disease. In total, 21 Czech, 7 Slovak, 9 Croatian and 7 Serbian patients (43 M/1 F) were included in the study (median age 11.0 years, range 1.2-43 years). Birth prevalence ranged from 1:69,223 (Serbia) to 1:192,626 (Czech Rep.). In the majority of patients (71%), the disease manifested in infancy. Cognitive functions were normal in 10 patients. Four, six and 24 patients had mild, moderate, and severe developmental delay, respectively, typically subsequent to developmental regression (59%). Residual enzyme activity showed no predictive value, and estimation of glycosaminoglycans (GAGs) had only limited importance for prognosis. Mutation analysis performed in 36 families led to the identification of 12 novel mutations, eight of which were small deletions/insertions. Large deletions/rearrangements and all but one small deletion/insertion led to a severe phenotype. This genotype-phenotype correlation was also identified in six cases with recurrent missense mutations. Based on patient genotype, the severity of the disease may be predicted with high probability in approximately half of MPS II patients.

• Klíčová slova
• Hunter syndrome, MPS II, Slavic origin, genotype-phenotype correlation, mucopolysaccharidosis type II,
• MeSH
• dítě MeSH
• dospělí MeSH
• genetické asociační studie MeSH
• glykoproteiny genetika   MeSH
• glykosaminoglykany moč   MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mukopolysacharidóza II etiologie   genetika   MeSH
• mutace * MeSH
• předškolní dítě MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Chorvatsko MeSH
• Slovenská republika MeSH
• Srbsko MeSH
• Názvy látek
• glykoproteiny MeSH
• glykosaminoglykany MeSH
• IDS protein, human MeSH Prohlížeč

AIM: The primary goal was to determine the yield of next-generation sequencing (NGS) epilepsy gene panels used for epilepsy etiology diagnosing using a multidisciplinary approach and to demonstrate the importance of genotype-phenotype correlations. The secondary goal was to evaluate the application of precision medicine in selected patients. METHODS: This single-center retrospective study included a total of 175 patients (95 males and 80 females) aged 0-19 years. They were examined between 2015 and 2020 using an NGS epilepsy gene panel (270 genes). A bioinformatic analysis was performed including copy number variation identification. Thorough genotype-phenotype correlation was performed. RESULTS: Out of 175 patients, described pathogenic variants or novel variants with clear pathogenic impact were identified in 30 patients (17.14%). Genotype-phenotype correlations and parental DNA analysis were performed, and genetic diagnosis was confirmed on the basis of the results in another 16 out of 175 patients (9.14%). The diagnostic yield of our study increased from 30 to 46 patients (by 53.33%) by the precise genotype-phenotype correlation. INTERPRETATION: We emphasize a complex genotype-phenotype correlation and a multidisciplinary approach in evaluating the results of the NGS epilepsy gene panel, which enables the most accurate genetic diagnosis and correct interpretation of results.

• Klíčová slova
• Children, Epilepsy, Genetic testing, Next-generation sequencing, Precise medicine,
• MeSH
• epilepsie * diagnóza   genetika   MeSH
• fenotyp MeSH
• genetické asociační studie MeSH
• genetické testování metody   MeSH
• lidé MeSH
• mutace MeSH
• retrospektivní studie MeSH
• variabilita počtu kopií segmentů DNA * MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Diamond Blackfan anemia (DBA) is predominantly an autosomal dominant inherited red cell aplasia primarily caused by pathogenic germline variants in ribosomal protein genes. DBA due to pathogenic RPL35A variants has been associated with large 3q29 deletions and phenotypes not common in DBA. We conducted a multi-institutional genotype-phenotype study of 45 patients with DBA associated with pathogenic RPL35A germline variants and curated the variant data on 21 additional cases from the literature. Genotype-phenotype analyses were conducted comparing patients with large deletions versus all other pathogenic variants in RPL35A. Twenty-two of the 45 cases had large deletions in RPL35A. After adjusting for multiple tests, a statistically significant association was observed between patients with a large deletion and steroid-resistant anemia, neutropenia, craniofacial abnormalities, chronic gastrointestinal problems, and intellectual disabilities (p<0.01) compared with all other pathogenic variants. Non-large deletion pathogenic variants were spread across RPL35A with no apparent hot spot and 56% of the individual family variants were observed more than once. In this, the largest known study of DBA patients with pathogenic RPL35A variants, we determined that patients with large deletions have a more severe phenotype that is clinically different from those with non-large deletion variants. Genes of interest also deleted in the 3q29 region that could be associated with some of these phenotypic features include LMLN and IQCG. Management of DBA due to large RPL35A deletions may be challenging due to complex problems and require comprehensive assessments by multiple specialists including immunologic, gastrointestinal, and developmental evaluations to provide optimal multidisciplinary care.

• MeSH
• Diamondova-Blackfanova anemie * genetika   MeSH
• fenotyp MeSH
• genetické asociační studie MeSH
• lidé MeSH
• mutace MeSH
• ribozomální proteiny genetika   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
• Názvy látek
• ribozomální proteiny MeSH
• RPL35A protein, human MeSH Prohlížeč

Autosomal recessive polycystic kidney disease (ARPKD) is a severe disease of early childhood that is clinically characterized by fibrocystic changes of the kidneys and the liver. The main cause of ARPKD are variants in the PKHD1 gene encoding the large transmembrane protein fibrocystin. The mechanisms underlying the observed clinical heterogeneity in ARPKD remain incompletely understood, partly due to the fact that genotype-phenotype correlations have been limited to the association of biallelic null variants in PKHD1 with the most severe phenotypes. In this observational study we analyzed a deep clinical dataset of 304 patients with ARPKD from two independent cohorts and identified novel genotype-phenotype correlations during childhood and adolescence. Biallelic null variants frequently show severe courses. Additionally, our data suggest that the affected region in PKHD1 is important in determining the phenotype. Patients with two missense variants affecting amino acids 709-1837 of fibrocystin or a missense variant in this region and a null variant less frequently developed chronic kidney failure, and patients with missense variants affecting amino acids 1838-2624 showed better hepatic outcome. Variants affecting amino acids 2625-4074 of fibrocystin were associated with poorer hepatic outcome. Thus, our data expand the understanding of genotype-phenotype correlations in pediatric ARPKD patients and can lay the foundation for more precise and personalized counselling and treatment approaches.

• Klíčová slova
• PKD, cilia, ciliopathies, fibrocystic hepatorenal disease, fibrocystin, polycystic kidney disease,
• MeSH
• dítě MeSH
• fenotyp MeSH
• genetické asociační studie MeSH
• ledviny MeSH
• lidé MeSH
• mutace MeSH
• polycystické ledviny autozomálně recesivní * diagnóza   genetika   MeSH
• předškolní dítě MeSH
• receptory buněčného povrchu genetika   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• PKHD1 protein, human MeSH Prohlížeč
• receptory buněčného povrchu 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.

• Klíčová slova
• PURA syndrome, epilepsy and seizures, hypotonia, intellectual disability, neonatal problems,
• 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
• Názvy látek
• DNA vazebné proteiny MeSH
• proteiny Drosophily MeSH
• Pur-alpha protein, Drosophila MeSH Prohlížeč
• PURA protein, human MeSH Prohlížeč
• transkripční faktory MeSH