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The term "recurrent constellations of embryonic malformations" (RCEM) is used to describe a number of multiple malformation associations that affect three or more body structures. The causes of these disorders are currently unknown, and no diagnostic marker has been identified. Consequently, providing a definitive diagnosis in suspected individuals is challenging. In this study, genome-wide DNA methylation analysis was conducted on DNA samples obtained from the peripheral blood of 53 individuals with RCEM characterized by clinical features recognized as VACTERL and/or oculoauriculovertebral spectrum association. We identified a common DNA methylation episignature in 40 out of the 53 individuals. Subsequently, a sensitive and specific binary classifier was developed based on the DNA methylation episignature. This classifier can facilitate the use of RCEM episignature as a diagnostic biomarker in a clinical setting. The study also investigated the functional correlation of RCEM DNA methylation relative to other genetic disorders with known episignatures, highlighting the common genomic regulatory pathways involved in the pathophysiology of RCEM., Competing Interests: Declaration of interests B.S. is a shareholder in EpiSign Inc. involved in commercial uses of EpiSign technology., (Copyright © 2024 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: Vesico-ureteral reflux (VUR) is a common associated urological anomaly in anorectal malformation (ARM)-patients. High-grade VUR requires antibiotic prophylaxis to prevent urinary tract infections (UTI's), renal scarring and -failure. The exact prevalence of high-grade VUR in ARM patients is unknown. Hence, the aim of this study was determining the incidence of high-grade VUR in ARM-patients, and its associated risk factors., Methods: A multicenter retrospective cohort study was performed using the ARM-Net registry, including data from 34 centers. Patient characteristics, screening for and presence of renal anomalies and VUR, sacral and spinal anomalies, and sacral ratio were registered. Phenotypes of ARM were grouped according to their complexity in complex and less complex. Multivariable analyses were performed to detect independent risk factors for high-grade (grade III-V) VUR., Results: This study included 2502 patients (50 % female). Renal screening was performed in 2250 patients (90 %), of whom 648 (29 %) had a renal anomaly documented. VUR-screening was performed in 789 patients (32 %), establishing high-grade VUR in 150 (19 %). In patients with a normal renal screening, high-grade VUR was still present in 10 % of patients. Independent risk factors for presence of high-grade VUR were a complex ARM (OR 2.6, 95 %CI 1.6-4.3), and any renal anomaly (OR 3.3, 95 %CI 2.1-5.3)., Conclusions: Although renal screening is performed in the vast majority of patients, only 32 % underwent VUR-screening. Complex ARM and any renal anomaly were independent risk factors for high-grade VUR. Remarkably, 10 % had high-grade VUR despite normal renal screening. Therefore, VUR-screening seems indicated in all ARM patients regardless of renal screening results, to prevent sequelae such as UTI's, renal scarring and ultimately renal failure., Type of Study: Observational Cohort-Study., Level of Evidence: III., Competing Interests: Conflict of interest None., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Congenital solitary functioning kidney (CSFK) is an anomaly predisposing to hypertension, albuminuria and chronic kidney disease. Its aetiology is complex and includes genetic and environmental factors. The role of gene-environment interactions (G×E), although relevant for other congenital anomalies, has not yet been investigated. Therefore, we performed a genome-wide G×E analysis with six preselected environmental factors to explore the role of these interactions in the aetiology of CSFK., Methods: In the AGORA (Aetiologic research into Genetic and Occupational/environmental Risk factors for Anomalies in children) data- and biobank, genome-wide single-nucleotide variant (SNV) data and questionnaire data on prenatal exposure to environmental risk factors were available for 381 CSFK patients and 598 healthy controls. Using a two-step strategy, we first selected independent significant SNVs associated with one of the six environmental risk factors. These SNVs were subsequently tested in G×E analyses using logistic regression models, with Bonferroni-corrected P-value thresholds based on the number of SNVs selected in step one., Results: In step one, 7-40 SNVs were selected per environmental factor, of which only rs3098698 reached statistical significance (P = .0016, Bonferroni-corrected threshold 0.0045) for interaction in step two. The interaction between maternal overweight and this SNV, which results in lower expression of the Arylsulfatase B (ARSB) gene, could be explained by lower insulin receptor activity in children heterozygous for rs3098698. Eight other G×E interactions had a P-value <.05, of which two were biologically plausible and warrant further study., Conclusions: Interactions between genetic and environmental factors may contribute to the aetiology of CSFK. To better determine their role, large studies combining data on genetic and environmental risk factors are warranted., (© The Author(s) 2023. Published by Oxford University Press on behalf of the ERA.)

A cross-sectional study was performed to evaluate health-related quality of life (HRQOL) in children with congenital vascular malformations (CVM) and to investigate factors associated with an impaired HRQOL. Children (2-17 years) with CVMs who visited the HECOVAN expertise center between 2016-2018 were included. The PedsQL 4.0 Generic Core Scales were used and a score ≥ 1.0 SD below the normative mean was defined as an impaired HRQOL. Factors associated with impairment were investigated using univariate and multivariate logistic regression analysis. The median overall HRQOL was 84.8/100 (n = 207; 41% boys, 59% girls; self-reported IQR 73.9-92.4 and parent-reported IQR 71.4-92.4). Patients aged 13-17 years reported significantly worse physical functioning than those aged 8-12 years (median 84.4, IQR 71.1-93.8 versus median 90.6, IQR 81.3-96.9; p = 0.02). Parents reported a significantly lower overall HRQOL than their children (median 80.4, IQR 70.7-90.8 versus median 85.9, IQR 76.1-92.4; p = 0.001). HRQOL was impaired in 25% of patients. Impairment occurred significantly more often in lower extremity CVMs (38%, p = 0.01) and multifocal CVMs (47%, p = 0.01) compared to CVMs in the head/neck region (13%). Other associated factors included invasive management (31% versus 14%; p = 0.01), age at first treatment ≤ 5 years (48% versus 25%; p = 0.02) and ongoing treatment (38% versus 18%; p = 0.004). After correction for other factors, significance remained for lower extremity CVMs and ongoing invasive treatment., Conclusions: Overall median HRQOL was reasonable and not significantly different from the norm sample. Parental ratings were significantly lower than their children's ratings. A quarter of the patients had an impaired HRQOL, which seemed to worsen with age. Independently associated factors included a lower extremity CVM and invasive management., What Is Known: • Congenital vascular malformations could affect health-related quality of life (HRQOL). • Studies on pediatric patients are limited and either very small or in combination with adult patient series., What Is New: • This study raises awareness of an impaired HRQOL in 25% of pediatric patients with congenital vascular malformations. • Associated factors included a lower extremity CVM and invasive management., (© 2023. The Author(s).)

Background: Registries are important in rare disease research. The Anorectal Malformation Network (ARM-Net) registry is a well-established European patient registry collecting demographic, clinical, and functional outcome data. We assessed the quality of this registry through review of the structure, data elements, collected data, and user experience., Material and Methods: Design and data elements were assessed for completeness, consistency, usefulness, accuracy, validity, and comparability. An intra- and inter-user variability study was conducted through monitoring and re-registration of patients. User experience was assessed via a questionnaire on registration, design of registry, and satisfaction., Results: We evaluated 119 data elements, of which 107 were utilized and comprised 42 string and 65 numeric elements. A minority (37.0%) of the 2278 included records had complete data, though this improved to 83.5% when follow-up elements were excluded. Intra-observer variability demonstrated 11.7% incongruence, while inter-observer variability was 14.7%. Users were predominantly pediatric surgeons and typically registered patients within 11-30 min. Users did not experience any significant difficulties with data entry and were generally satisfied with the registry, but preferred more longitudinal data and patient-reported outcomes., Conclusions: The ARM-Net registry presents one of the largest ARM cohorts. Although its collected data are valuable, they are susceptible to error and user variability. Continuous evaluations are required to maintain relevant and high-quality data and to achieve long-term sustainability. With the recommendations resulting from this study, we call for rare disease patient registries to take example and aim to continuously improve their data quality to enhance the small, but impactful, field of rare disease research., Level of Evidence: V., Competing Interests: Declaration of competing interest None., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The etiology of congenital solitary functioning kidney (CSFK) is largely unknown but likely includes various risk factors. We performed a case-control study to compare exposure to environmental and parental risk factors during embryonic kidney development between children with CSFK and healthy controls., Methods: We included 434 children with CSFK and 1302 healthy controls from the AGORA data- and biobank matched on year of birth. Exposure to potential risk factors was investigated using parental questionnaire data. Crude and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were estimated for each potential risk factor. Multiple imputation was used to deal with missing values. Confounders for each potential risk factor were selected using directed acyclic graphs., Results: Maternal stress was newly identified as a risk factor for CSFK (aOR 2.1, 95% CI 1.2-3.5). Known associations with conception using in vitro fertilization/intracytoplasmic sperm injection (aOR 1.8, 95% CI 1.0-3.2), maternal infections during pregnancy (aOR 2.5, 95% CI 1.4-4.7), smoking during pregnancy (aOR 1.4, 95% CI 1.0-2.0), and parental CAKUT (aOR 6.6, 95% CI 2.9-15.1) were confirmed, but previous associations with diabetes and obesity could not be replicated. Folic acid supplement use and younger maternal age seemed to reduce the risk of CSFK (aORs 0.7, 95% CI 0.5-1.0, and 0.8, 95% CI 0.6-1.0, respectively)., Conclusions: Environmental and parental risk factors are likely to be involved in the development of CSFK and future studies should combine genetic, environmental, and gene-environment interaction analyses. Women wanting to become pregnant should consider optimizing their health and lifestyle. A higher-resolution version of the Graphical abstract is available as Supplementary information., (© 2023. The Author(s).)

Purpose: To assess the number, characteristics, and functional short-, and midterm outcomes of patients with rectal atresia (RA) and stenosis (RS) in the ARM-Net registry., Methods: Patients with RA/RS were retrieved from the ARM-Net registry. Patient characteristics, associated anomalies, surgical approach, and functional bowel outcomes at 1 and 5-year follow-up were assessed., Results: The ARM-Net registry included 2619 patients, of whom 36 (1.3%) had RA/RS. Median age at follow-up was 7.0 years (IQR 2.3-9.0). Twenty-three patients (63.9%, RA n = 13, RS n = 10) had additional anomalies. PSARP was the most performed reconstructive surgery for both RA (n = 9) and RS (n = 6) patients. At 1-year follow-up, 11/24 patients with known data (45.8%, RA n = 5, RS n = 6) were constipated, of whom 9 required stool softeners and/or laxatives. At 5-year follow-up, 8/9 patients with known data (88.9%, RA n = 4, RS n = 4) were constipated, all requiring laxatives and/or enema., Conclusion: RA and RS are rare types of ARM, representing 1.3% of patients in the ARM-Net registry. Additional anomalies were present in majority of patients. Different surgical approaches were performed as reconstructive treatment, with constipation occurring in 46% and 89% of the patients at 1 and 5-year follow-up. However, accurate evaluation of long-term functional outcomes remains challenging., (© 2023. The Author(s).)

Patient registries serve to overcome the research limitations inherent in the study of rare diseases, where patient numbers are typically small. Despite the value of real-world data collected through registries, adequate design and maintenance are integral to data quality. We aimed to describe an overview of the challenges in design, quality management, and maintenance of rare disease registries.A systematic search of English articles was conducted in PubMed, Ovid Medline/Embase, and Cochrane Library. Search terms included "rare diseases, patient registries, common data elements, quality, hospital information systems, and datasets". Inclusion criteria were any manuscript type focused upon rare disease patient registries describing design, quality monitoring or maintenance. Biobanks and drug surveillances were excluded.A total of 37 articles, published between 2001 and 2021, met the inclusion criteria. Patient registries covered a wide range of disease areas and covered multiple geographical locations, with a predisposition for Europe. Most articles were methodological reports and described the design and setup of a registry. Most registries recruited clinical patients (92%) with informed consent (81%) and protected the collected data (76%). Whilst the majority (57%) collected patient-reported outcome measures, only few (38%) consulted PAGs during the registry design process. Few reports described details regarding quality management (51%) and maintenance (46%).Rare disease patient registries are valuable for research and evaluation of clinical care, and an increasing number have emerged. However, registries need to be continuously evaluated for data quality and long-term sustainability to remain relevant for future use., (© 2023. The Author(s).)

Introduction: Posterior urethral valves (PUV) is a congenital disorder causing an obstruction of the lower urinary tract that affects approximately 1 in 4,000 male live births. PUV is considered a multifactorial disorder, meaning that both genetic and environmental factors are involved in its development. We investigated maternal risk factors for PUV., Methods: We included 407 PUV patients and 814 controls matched on year of birth from the AGORA data- and biobank and three participating hospitals. Information on potential risk factors (family history of congenital anomalies of the kidney and urinary tract (CAKUT), season of conception, gravidity, subfertility, and conception using assisted reproductive techniques (ART), plus maternal age, body mass index, diabetes, hypertension, smoking, and use of alcohol and folic acid) was derived from maternal questionnaires. After multiple imputation, adjusted odds ratios (aORs) were estimated using conditional logistic regression corrected for minimally sufficient sets of confounders determined using directed acyclic graphs., Results: A positive family history and low maternal age (<25 years) were associated with PUV development [aORs: 3.3 and 1.7 with 95% confidence intervals (95% CI) 1.4-7.7 and 1.0-2.8, respectively], whereas higher maternal age (>35 years) was associated with a lower risk (aOR: 0.7 95% CI: 0.4-1.0). Maternal preexisting hypertension seemed to increase PUV risk (aOR: 2.1 95% CI: 0.9-5.1), while gestational hypertension seemed to decrease this risk (aOR: 0.6 95% CI: 0.3-1.0). Concerning use of ART, the aORs for the different techniques were all above one, but with very wide 95% CIs including one. None of the other factors studied were associated with PUV development., Conclusion: Our study showed that family history of CAKUT, low maternal age, and potentially preexisting hypertension were associated with PUV development, whereas higher maternal age and gestational hypertension seemed to be associated with a lower risk. Maternal age and hypertension as well as the possible role of ART in the development of PUV require further research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 van der Zanden, Groen In ‘t Woud, van Rooij, Quaedackers, Steffens, de Wall, Schreuder, Feitz and Roeleveld.)

Congenital solitary functioning kidney (CSFK) is a birth defect that occurs in 1:1500 children and predisposes them to kidney injury. Its aetiology is likely multifactorial. In addition to known monogenic causes and environmental risk factors, common genetic variation may contribute to susceptibility to CSFK. We performed a genome-wide association study among 452 patients with CSFK and two control groups of 669 healthy children and 5363 unaffected adults. Variants in two loci reached the genome-wide significance threshold of 5 × 10 -8 , and variants in 30 loci reached the suggestive significance threshold of 1 × 10 -5 . Of these, an identified locus with lead single nucleotide variant (SNV) rs140804918 (odds ratio 3.1, p -value = 1.4 × 10 -8 ) on chromosome 7 was most promising due to its close proximity to HGF , a gene known to be involved in kidney development. Based on their known molecular functions, both KCTD20 and STK38 could explain the suggestive significant association with lead SNV rs148413365 on chromosome 6. Our findings need replication in an independent cohort of CSFK patients before they can be established definitively. However, our analysis suggests that common variants play a role in CSFK aetiology. Future research could enhance our understanding of the molecular mechanisms involved.

Classic bladder exstrophy represents the most severe end of all human congenital anomalies of the kidney and urinary tract and is associated with bladder cancer susceptibility. Previous genetic studies identified one locus to be involved in classic bladder exstrophy, but were limited to a restrict number of cohort. Here we show the largest classic bladder exstrophy genome-wide association analysis to date where we identify eight genome-wide significant loci, seven of which are novel. In these regions reside ten coding and four non-coding genes. Among the coding genes is EFNA1, strongly expressed in mouse embryonic genital tubercle, urethra, and primitive bladder. Re-sequence of EFNA1 in the investigated classic bladder exstrophy cohort of our study displays an enrichment of rare protein altering variants. We show that all coding genes are expressed and/or significantly regulated in both mouse and human embryonic developmental bladder stages. Furthermore, nine of the coding genes residing in the regions of genome-wide significance are differentially expressed in bladder cancers. Our data suggest genetic drivers for classic bladder exstrophy, as well as a possible role for these drivers to relevant bladder cancer susceptibility., (© 2022. The Author(s).)

Congenital lower urinary tract obstructions (LUTO) are most often caused by posterior urethral valves (PUV), a male limited anatomical obstruction of the urethra affecting 1 in 4,000 male live births. Little is known about the genetic background of PUV. Here, we report the largest genome-wide association study (GWAS) for PUV in 4 cohorts of patients and controls. The final meta-analysis included 756 patients and 4,823 ethnicity matched controls and comprised 5,754,208 variants that were genotyped or imputed and passed quality control in all 4 cohorts. No genome-wide significant locus was identified, but 33 variants showed suggestive significance ( P < 1 × 10 -5 ). When considering only loci with multiple variants residing within < 10 kB of each other showing suggestive significance and with the same effect direction in all 4 cohorts, 3 loci comprising a total of 9 variants remained. These loci resided on chromosomes 13, 16, and 20. The present GWAS and meta-analysis is the largest genetic study on PUV performed to date. The fact that no genome-wide significant locus was identified, can be explained by lack of power or may indicate that common variants do not play a major role in the etiology of PUV. Nevertheless, future studies are warranted to replicate and validate the 3 loci that yielded suggestive associations., Competing Interests: Author SH was employed by Life&Brain GmbH. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 van der Zanden, Maj, Borisov, van Rooij, Quaedackers, Steffens, Schierbaum, Schneider, Waffenschmidt, Kiemeney, de Wall, Heilmann, Hofmann, Gehlen, Schumacher, Szczepanska, Taranta-Janusz, Kroll, Krzemien, Szmigielska, Schreuder, Weber, Zaniew, Roeleveld, Reutter, Feitz and Hilger.)

In the past, an anteriorly located anus was often misdiagnosed and treated as an anorectal malformation (ARM) with a perineal fistula (PF). The paper aims to define the criteria for a normal anus, an anterior anus (AA) as an anatomic variant, and milder types of ARM such as congenital anal stenosis (CAS) and PF. An extensive literature search was performed by a working group of the ARM-Net Consortium concerning the subject "Normal Anus, AA, and mild ARM". A consensus on definitions, clinical characteristics, diagnostic management, and treatment modalities was established, and a diagnostic algorithm was proposed. The algorithm enables pediatricians, midwives, gynecologists, and surgeons to make a timely correct diagnosis of any abnormally looking anus and initiate further management if needed. Thus, the routine physical inspection of a newborn should include the inspection of the anus and define its position, relation to the external sphincter, and caliber. A correct diagnosis and use of the presented terminology will avoid misclassifications and allow the initiation of correct management. This will provide a reliable comparison of different therapeutic management and outcomes of these patient cohorts in the future.

Background: Challenges faced by children diagnosed with a rare disease or complex condition and their family members are often characterized by disease-specific complexities, such as a prolonged diagnostic process, an uncertain prognosis, and the absence of curative treatment. The psychological burden of living with a rare disease or complex condition is often understudied and may present overarching concepts that shape the general experience of having been diagnosed with a rare condition. The present study examines common needs from a comprehensive perspective combining relevant aspects from the rare disease literature in a theoretical perspective from pediatric psychology, such as a family-centred, developmental and interdisciplinary approach. An exploratory study was designed among parents from children with a rare disease or complex condition in an Integrated University Children's Hospital in the Netherlands. Semi-structured interviews were conducted with open-ended questions based around the experience of having a child diagnosed with a rare condition, such as the psychosocial impact on the child and it's development, the impact on the family, and how provided care was experienced., Results: Twelve interviews were analysed with a thematic content analysis to identify common needs. Eight themes followed from the analysis and uncovered the need for (1) family-focused care, (2) coping with uncertainty, (3) empathic communication, (4) practical support, (5) information, (6) psychological support, (7) interdisciplinary care, and (8) social support., Conclusions: The results from our study provide directions for research and health care to support young patients with a rare disease or complex condition and their families. Moreover, our results demonstrated that there are overarching concepts across different rare diseases that may be optimally supported with interdisciplinary care., (© 2022. The Author(s).)

The caudal type homeobox 2 (CDX2) gene encodes a developmental regulator involved in caudal body patterning. Only three pathogenic variants in human CDX2 have been described, in patients with persistent cloaca, sirenomelia and/or renal and anogenital malformations. We identified five patients with de novo or inherited pathogenic variants in CDX2 with clinical phenotypes that partially overlap with previous cases, that is, imperforate anus and renal, urogenital and limb abnormalities. However, additional clinical features were seen including vertebral agenesis and we describe considerable phenotypic variability, even in unrelated patients with the same recurrent p.(Arg237His) variant. We propose CDX2 variants as rare genetic cause for a multiple congenital anomaly syndrome that can include features of caudal regression syndrome and VACTERL. A causative role is further substantiated by the relationship between CDX2 and other proteins encoded by genes that were previously linked to caudal abnormalities in humans, for example, TBXT (sacral agenesis and other vertebral segmentation defects) and CDX1 (anorectal malformations). Our findings confirm the essential role of CDX2 in caudal morphogenesis and formation of cloacal derivatives in humans, which to date has only been well characterized in animals., (© 2021 The Authors. Clinical Genetics published by John Wiley & Sons Ltd.)

Anorectal malformation (ARM) is a relatively frequently occurring congenital anomaly of hindgut development with a prevalence of 1 in 3,000 live births. ARM may present as an isolated anomaly, but it can also be associated with other anomalies, sometimes as part of a recognizable syndrome. After birth, much medical attention is given to the treatment and restoring of bowel function in children with ARM. Effort should also be given to studying the etiology of the ARM in these patients. This information is important to both the medical community and the family, because it can help guide treatment and provides information on the long-term prognosis of the patient and recurrence risk in the family.In this article, we will review the current knowledge on the (genetic) etiology of (syndromic) ARM and provide guidelines for (family) history taking and clinical and genetic studies of ARM patients and their families, which is needed to study the causal factors in an ARM patient and for genetic counseling of the families., Competing Interests: None declared., (Thieme. All rights reserved.)

Background/purpose: Parental decisional conflict and decisional regret are aspects in parental adjustment to childhood elective surgery. This study assessed correlates of parental decisional regret in parents of young boys treated for hypospadias., Methods: Parents of 261 boys treated for hypospadias at the Radboudumc between 2006 and 2014 were approached to complete questionnaires on socio-demographics, clinical details, postoperative outcomes, decisional conflict and decisional regret., Results: Of the 97 participating parents, 50.5% reported some form of decisional regret, in 11.3% this was moderate to strong. Decisional conflict (β = .68, p < .001) and psychosocial behavior problems of the child (β = .20, p < .05) significantly predicted decisional regret. Demographic and medical variables did not correlate with parental decisional regret., Conclusions: A substantial number of parents report some form of decisional regret regarding the elective surgery for hypospadias in their child. Although most parents only show mild forms of regret, in the perspective of discussions on this surgery in early childhood, future research could shed more light on the interrelationship between medical and psychosocial factors in the process of decision-making around surgery, in boys with hypospadias and their parents., (Copyright © 2021. Published by Elsevier Ltd.)

Anorectal malformations (ARM) represent a rare birth defect of the hindgut that occur in approximately 1 in 3000 live births. Around 60% of ARM occur with associated anomalies including defined genetic syndromes and associations with chromosomal aberrations. The etiology of ARM is heterogeneous, with the individual environmental or genetic risk factors remaining unknown for the majority of cases. The occurrence of familial ARM and previous epidemiologic analysis suggest autosomal dominant inheritance in a substantial subset of ARM patients. The implicated mortality and reduced fecundity in patients with ARM would lead to allele loss. However, mutational de novo events among the affected individuals could compensate for the evolutionary pressure. With the implementation of exome sequencing, array-based molecular karyotyping and family-based rare variant analyses, the technologies are available to identify the respective factors. This review discusses the identification of disease-causing variants among individuals with ARM. It highlights the role of mutational de novo events.

Background: Posterior urethral valves (PUVs) and ureteropelvic junction obstruction (UPJO) are congenital obstructive uropathies that may impair kidney development., Objective: To identify genetic variants associated with kidney injury in patients with obstructive uropathy., Design Setting and Participants: We included 487 patients born in 1981 or later who underwent pyeloplasty or valve resection before 18 yr of age in the discovery phase, 102 PUV patients in a first replication phase, and 102 in a second replication phase., Outcome Measurements and Statistical Analysis: Signs of kidney injury were defined as dialysis, nephrectomy, kidney transplantation, estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m 2 , high blood pressure, antihypertensive medication use, proteinuria, and/or one kidney functioning at <45%. We used χ 2 tests to calculate p values and odds ratios for >600 000 single-nucleotide polymorphisms (SNPs) in the discovery sample comparing patients with and without signs of kidney injury within 5 yr after surgery. We performed stratified analyses for PUV and UPJO and Kaplan-Meier and Cox regression analyses in the discovery and two replication samples for the associated SNPs, and RNA and protein expression analyses for the associated gene in fetal tissues., Results and Limitations: Despite the small and nonhomogeneous sample, we observed suggestive associations for six SNPs in three loci, of which rs6874819 in the CDH12 gene was the most clear ( p  = 7.5 × 10 -7 ). This SNP also seemed to be associated with time to kidney injury in the PUV discovery and replication samples. RNA expression analyses showed clear CDH12 expression in fetal kidneys, which was confirmed by protein immunolocalization., Conclusions: This study identified CDH12 as a candidate gene for kidney injury in PUV., Patient Summary: We found that variants of the CDH12 gene increase the risk of kidney injury in patients with extra flaps of tissue in the urethra (posterior urethral valves). This is the first report on this gene in this context. Our study provides interesting new information about the pathways involved and important leads for further research for this condition., (© 2021 The Author(s).)

We describe and evaluate our practice-based learning approach for research in undergraduate students studying Biomedical Sciences at Radboud University Nijmegen, the Netherlands. First-year students who started their study between 2015 and 2018 actively participated in data collection and measurements, including anthropometry, electrocardiogram findings, genetic variants, and lifestyle habits. All data were entered into one anonymous database , which was used by students to analyze their research questions. In 2019, 44 of the 87 students (50%) valued active measurements better than questionnaires. Most students (strongly) agreed that they have learned about data collection and were inspired to learn more about biomedical research., (© The Author(s) 2021.)

Background: Hypospadias is a frequently occurring congenital anomaly in male infants, in which the opening of the urethra is located along the ventral side of the penis. Although various studies attempted to identify its causes, the aetiology of the majority of hypospadias cases remains poorly understood. Maternal hypertensive disorders are believed to be associated with hypospadias, but the results of previous studies are not consistent, especially for subtypes of hypospadias., Objectives: To investigate the associations between maternal hypertensive disorders, stratified by pharmacological treatment, and the occurrence of hypospadias divided into subtypes in a large population-based case-control study., Methods: We included 887 hypospadias cases and 1005 male controls from the AGORA data- and biobank. Cases and controls were born in the periods 1975-2016 and 1990-2011, respectively. All data were collected in the period 2004-2018. Maternal questionnaires were used to obtain information on hypertensive disorders during pregnancy, antihypertensive medication treatment, and potential confounders. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for the associations between hypertensive disorders and hypospadias were estimated using logistic regression., Results: Hypertensive disorders were reported by 15.3% of the women in this study. Maternal hypertensive disorders in general, chronic hypertension, and gestational hypertension were not associated with hypospadias or its subtypes. Preeclampsia was associated with posterior hypospadias (aOR 3.09, 95% CI 1.49, 6.43), whether it was untreated (aOR 2.81, 95% CI 1.24, 6.38) or pharmacologically treated preeclampsia (aOR 4.96, 95% CI 1.08, 22.80)., Conclusions: Our findings indicate that preeclampsia is associated with posterior hypospadias, irrespective of pharmacological treatment. This result supports the hypothesis of aetiological heterogeneity among the subtypes of hypospadias, with pregnancy-related risk factors being associated with the more severe types of hypospadias., (© 2020 The Authors. Paediatric and Perinatal Epidemiology published by John Wiley & Sons Ltd.)

Background: The VACTERL association (VACTERL) includes at least three of these congenital anomalies: vertebral, anal, cardiac, trachea-esophageal, renal, and limb anomalies. Assisted reproductive techniques (ART), pregestational diabetes mellitus, and chronic lower obstructive pulmonary disorders (CLOPD) have been associated with VACTERL. We aimed to replicate these findings and were interested in additional maternal risk factors., Methods: A case-control study using self-administered questionnaires was performed including 142 VACTERL cases and 2,135 population-based healthy controls. Multivariable logistic regression analyses were performed to estimate confounder adjusted odds ratios (aOR) and 95% confidence intervals (95%CI)., Results: Parents who used invasive ART had an increased risk of VACTERL in offspring (aOR 4.4 [95%CI 2.1-8.8]), whereas the increased risk for mothers with CLOPD could not be replicated. None of the case mothers had pregestational diabetes mellitus. Primiparity (1.5 [1.1-2.1]) and maternal pregestational overweight and obesity (1.8 [1.2-2.8] and 1.8 [1.0-3.4]) were associated with VACTERL. Consistent folic acid supplement use during the advised periconceptional period may reduce the risk of VACTERL (0.5 [0.3-1.0]). Maternal smoking resulted in an almost twofold increased risk of VACTERL., Conclusion: We identified invasive ART, primiparity, pregestational overweight and obesity, lack of folic acid supplement use, and smoking as risk factors for VACTERL., (© 2020 The Authors. Birth Defects Research published by Wiley Periodicals LLC.)

Aim: Male patients with anorectal malformations (ARM) are classified according to presence and level of the recto-urinary fistula. This is traditionally established by a preoperative high-pressure distal colostogram that may be variably interpreted by different surgeons. The aim of this study was to evaluate the inter- and intraobserver variation in the assessment by pediatric surgeons of preoperative colostograms with respect to the level of the recto-urinary fistula. Materials and Methods: Sixteen pediatric surgeons from 14 European centers belonging to the ARM-Net Consortium twice scored 130 images of distal colostograms taken in sagittal projection at a median age of 66 days of life (range: 4-1,106 days). Surgeons were asked to classify the fistula in bulbar, prostatic, bladder-neck, no fistula, and "unclear anatomy" example. Their assessments were compared with the intraoperative findings (kappa) for two scoring rounds with an interval of 6 months (intraobserver variation). Agreement among the surgeons' scores (interobserver variation) was also calculated using Krippendorff's alpha. A kappa over 0.75 is considered excellent, between 0.40 and 0.75 fair to good, and below 0.40 poor. Surgeons were asked to score the images in "poor" and "good" quality and to provide their years of experience in ARM treatment. Results: Agreement between the image-based rating of surgeons and the intraoperative findings ranges from 0.06 to 0.45 (mean 0.31). Interobserver variation is higher (Krippendorff's alpha between 0.40 and 0.45). Years of experience in ARM treatment does not seem to influence the scoring. The mean intraobserver variation between the two rounds is 0.64. Overall, the quality of the images is considered poor. Images categorized as having a good quality result in a statistically significant higher kappa (mean: 0.36 and 0.37 in the first and second round, respectively) than in the group of bad-quality images (mean: 0.25 and 0.23, respectively). Conclusions: There is poor agreement among experienced pediatric colorectal surgeons on preoperative colostograms. Techniques and analyses of images need to be improved in order to generate a homogeneous series of patients and make comparison of outcomes reliable., (Copyright © 2020 Midrio, van Rooij, Brisighelli, Garcia, Fanjul, Broens, Iacobelli, Giné, Lisi, Sloots, Fascetti Leon, Morandi, van der Steeg, Giuliani, Grasshoff-Derr, Lacher, de Blaauw and Jenetzky.)

Previous studies in developing Xenopus and zebrafish reported that the phosphate transporter slc20a1a is expressed in pronephric kidneys. The recent identification of SLC20A1 as a monoallelic candidate gene for cloacal exstrophy further suggests its involvement in the urinary tract and urorectal development. However, little is known of the functional role of SLC20A1 in urinary tract development. Here, we investigated this using morpholino oligonucleotide knockdown of the zebrafish ortholog slc20a1a . This caused kidney cysts and malformations of the cloaca. Moreover, in morphants we demonstrated dysfunctional voiding and hindgut opening defects mimicking imperforate anus in human cloacal exstrophy. Furthermore, we performed immunohistochemistry of an unaffected 6-week-old human embryo and detected SLC20A1 in the urinary tract and the abdominal midline, structures implicated in the pathogenesis of cloacal exstrophy. Additionally, we resequenced SLC20A1 in 690 individuals with bladder exstrophy-epispadias complex (BEEC) including 84 individuals with cloacal exstrophy. We identified two additional monoallelic de novo variants. One was identified in a case-parent trio with classic bladder exstrophy, and one additional novel de novo variant was detected in an affected mother who transmitted this variant to her affected son. To study the potential cellular impact of SLC20A1 variants, we expressed them in HEK293 cells. Here, phosphate transport was not compromised, suggesting that it is not a disease mechanism. However, there was a tendency for lower levels of cleaved caspase-3, perhaps implicating apoptosis pathways in the disease. Our results suggest SLC20A1 is involved in urinary tract and urorectal development and implicate SLC20A1 as a disease-gene for BEEC., (Copyright © 2020 Rieke, Zhang, Braun, Yilmaz, Japp, Lopes, Pleschka, Hilger, Schneider, Newman, Beaman, Nordenskjöld, Ebert, Promm, Rösch, Stein, Hirsch, Schäfer, Schmiedeke, Boemers, Lacher, Kluth, Gosemann, Anderberg, Barker, Holmdahl, Läckgren, Keene, Cervellione, Giorgio, Di Grazia, Feitz, Marcelis, Van Rooij, Bökenkamp, Beckers, Keegan, Sharma, Dakal, Wittler, Grote, Zwink, Jenetzky, Brusco, Thiele, Ludwig, Schweizer, Woolf, Odermatt and Reutter.)

Background: The VATER/VACTERL association (VACTERL) is defined as the non-random occurrence of the following congenital anomalies: Vertebral, Anal, Cardiac, Tracheal-Esophageal, Renal, and Limb anomalies. As no unequivocal candidate gene has been identified yet, patients are diagnosed phenotypically. The aims of this study were to identify patients with monogenic disorders using a genetics-first approach, and to study whether variants in candidate genes are involved in the etiology of VACTERL or the individual features of VACTERL: Anorectal malformation (ARM) or esophageal atresia with or without trachea-esophageal fistula (EA/TEF). Methods: Using molecular inversion probes, a candidate gene panel of 56 genes was sequenced in three patient groups: VACTERL ( n = 211), ARM ( n = 204), and EA/TEF ( n = 95). Loss-of-function (LoF) and additional likely pathogenic missense variants, were prioritized and validated using Sanger sequencing. Validated variants were tested for segregation and patients were clinically re-evaluated. Results: In 7 out of the 510 patients (1.4%), pathogenic or likely pathogenic variants were identified in SALL1, SALL4 , and MID1 , genes that are associated with Townes-Brocks, Duane-radial-ray, and Opitz-G/BBB syndrome. These syndromes always include ARM or EA/TEF, in combination with at least two other VACTERL features. We did not identify LoF variants in the remaining candidate genes. Conclusions: None of the other candidate genes were identified as novel unequivocal disease genes for VACTERL. However, a genetics-first approach allowed refinement of the clinical diagnosis in seven patients, in whom an alternative molecular-based diagnosis was found with important implications for the counseling of the families., (Copyright © 2020 van de Putte, Dworschak, Brosens, Reutter, Marcelis, Acuna-Hidalgo, Kurtas, Steehouwer, Dunwoodie, Schmiedeke, Märzheuser, Schwarzer, Brooks, de Klein, Sloots, Tibboel, Brisighelli, Morandi, Bedeschi, Bates, Levitt, Peña, de Blaauw, Roeleveld, Brunner, van Rooij and Hoischen.)

Introduction: Several medical and surgical improvements in the treatment of congenital diaphragmatic hernia (CDH) patients have led to a higher survival rate. However, some of these improvements also lead to an increased morbidity rate. This study aims to determine the contribution different medical and surgical treatments have had on the development of surgical complications., Method: All CDH patients treated in a single centre between 2000 and 2015 were retrospectively evaluated. Multivariate logistic regression was used to estimate the independent effects of several treatment options that could influence the surgical outcome by adjustment for multiple risk factors., Results: Sixty of the 197 surgically repaired CDH patients had surgical complications. There were more haemorrhagic complications in the ECMO compared to non-ECMO group (27% vs. 2%, p < 0.001). The use of inhaled nitric oxide was also significantly related to haemorrhage (OR = 13.0 (95% CI 1.1-159)). After adjustment for other risk factors, chylothorax was neither significantly associated with ECMO treatment (OR = 1.6 (95% CI 0.5-5.2) nor with patch repair (OR = 2.1: 95% CI 0.7-6.1). A recurrence occurred more often in patients with pulmonary hypertension (OR = 10.0 (95% CI 1.5-65.8) and after treatment with an abdominal patch (OR = 11.3: 95% CI 1.5-84.4)., Conclusion: ECMO treatment and the inhalation of nitric oxide are used in the most severe CDH patients but are associated with a higher risk on surgical haemorrhage. The recurrence rate is associated with both the use of an abdominal patch and the presence of pulmonary hypertension, regardless of medical treatment.

Background: The VACTERL association (VACTERL) is the nonrandom occurrence of at least three of these congenital anomalies: vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies. Despite suggestions for involvement of several genes and nongenetic risk factors from small studies, the etiology of VACTERL remains largely unknown., Objective: To identify maternal risk factors for VACTERL in offspring in a large European study., Methods: A case-control study was performed using data from 28 EUROCAT registries over the period 1997-2015 with case and control ascertainment through hospital records, birth and death certificates, questionnaires, and/or postmortem examinations. Cases were diagnosed with VACTERL, while controls had a genetic syndrome and/or chromosomal abnormality. Data collected included type of birth defect and maternal characteristics, such as age, use of assisted reproductive techniques (ART), and chronic illnesses. Multivariable logistic regression analyses were performed to estimate confounder adjusted odds ratios (aOR) with 95% confidence intervals (95% CI)., Results: The study population consisted of 329 VACTERL cases and 49,724 controls with recognized syndromes or chromosomal abnormality. For couples who conceived through ART, we found an increased risk of VACTERL (aOR 2.3 [95% CI 1.3, 3.9]) in offspring. Pregestational diabetes (aOR 3.1 [95% CI 1.1, 8.6]) and chronic lower obstructive pulmonary diseases (aOR 3.9 [95% CI 2.2, 6.7]) also increased the risk of having a child with VACTERL. Twin pregnancies were not associated with VACTERL (aOR 0.6 [95% CI 0.3, 1.4])., Conclusion: We identified several maternal risk factors for VACTERL in offspring befitting a multifactorial etiology., (© 2020 The Authors. Birth Defects Research published by Wiley Periodicals, Inc.)

Background: The VACTERL (Vertebral anomalies, Anal atresia, Cardiac malformations, Tracheo-Esophageal fistula, Renal anomalies, Limb abnormalities) association is the non-random occurrence of at least three of these congenital anomalies: vertebral, anal, cardiac, tracheo-esophageal, renal, and limb anomalies. Diagnosing VACTERL patients is difficult, as many disorders have multiple features in common with VACTERL. The aims of this study were to clearly outline component features, describe the phenotypic spectrum among the largest group of VACTERL patients thus far reported, and to identify phenotypically similar subtypes., Methods: A case-only study was performed assessing data on 501 cases recorded with VACTERL in the JRC-EUROCAT (Joint Research Centre-European Surveillance of Congenital Anomalies) central database (birth years: 1980-2015). We differentiated between major and minor VACTERL features and anomalies outside the VACTERL spectrum to create a clear definition of VACTERL., Results: In total, 397 cases (79%) fulfilled our VACTERL diagnostic criteria. The most commonly observed major VACTERL features were anorectal malformations and esophageal atresia/tracheo-esophageal fistula (both occurring in 62% of VACTERL cases), followed by cardiac (57%), renal (51%), vertebral (33%), and limb anomalies (25%), in every possible combination. Three VACTERL subtypes were defined: STRICT-VACTERL, VACTERL-LIKE, and VACTERL-PLUS, based on severity and presence of additional congenital anomalies., Conclusion: The clearly defined VACTERL component features and the VACTERL subtypes introduced will improve both clinical practice and etiologic research.

Background: The impact of perioperative care interventions on postreconstructive complications and short-term colorectal outcome in patients with anorectal malformation (ARM) type rectovestibular fistula is unknown., Methods: An ARM-Net consortium multicenter retrospective cohort study was performed including 165 patients with a rectovestibular fistula. Patient characteristics, perioperative care interventions, timing of reconstruction, postreconstructive complications and the colorectal outcome at one year of follow-up were registered., Results: Overall complications were seen in 26.8% of the patients, of which 41% were regarded major. Differences in presence of enterostomy, timing of reconstruction, mechanical bowel preparation, antibiotic prophylaxis and postoperative feeding regimen had no impact on the occurrence of overall complications. However, mechanical bowel preparation, antibiotic prophylaxis ≥48 h and postoperative nil by mouth showed a significant reduction in major complications. The lowest rate of major complications was found in the group having these three interventions combined (5.9%). Multivariate analyses did not show independent significant results of any of the perioperative care interventions owing to center-specific combinations. At one year follow-up, half of the patients experienced constipation and this was significantly higher among those with preoperative mechanical bowel preparation., Conclusions: Differences in perioperative care interventions do not seem to impact the incidence of overall complications in a large cohort of European rectovestibular fistula-patients. Mechanical bowel preparation, antibiotic prophylaxis ≥48 h, and postoperative nil by mouth showed the least major complications. Independency could not be established owing to center-specific combinations of interventions., Type of Study: Treatment study., Level of Evidence: III., (Copyright © 2019 Elsevier Inc. All rights reserved.)

We aimed to identify novel deletions and variants of TP63 associated with orofacial clefting (OFC). Copy number variants were assessed in three OFC families using microarray analysis. Subsequently, we analyzed TP63 in a cohort of 1072 individuals affected with OFC and 706 population-based controls using molecular inversion probes (MIPs). We identified partial deletions of TP63 in individuals from three families affected with OFC. In the OFC cohort, we identified several TP63 variants predicting to cause loss-of-function alleles, including a frameshift variant c.569&#95;576del (p.(Ala190Aspfs*5)) and a nonsense variant c.997C>T (p.(Gln333*)) that introduces a premature stop codon in the DNA-binding domain. In addition, we identified the first missense variants in the oligomerization domain c.1213G>A (p.(Val405Met)), which occurred in individuals with OFC. This variant was shown to abrogate oligomerization of mutant p63 protein into oligomeric complexes, and therefore likely represents a loss-of-function allele rather than a dominant-negative. All of these variants were inherited from an unaffected parent, suggesting reduced penetrance of such loss-of-function alleles. Our data indicate that loss-of-function alleles in TP63 can also give rise to OFC as the main phenotype. We have uncovered the dosage-dependent functions of p63, which were previously rejected.

Introduction: Anorectal malformations (ARM) are rare congenital malformations, resulting from disturbed hindgut development. A genetic etiology has been suggested, but evidence for the involvement of specific genes is scarce. We evaluated the contribution of rare and low-frequency coding variants in ARM etiology, assuming a multifactorial model., Methods: We analyzed 568 Caucasian ARM patients and 1,860 population-based controls using the Illumina HumanExome Beadchip array, which contains >240,000 rare and low-frequency coding variants. GenomeStudio clustering and calling was followed by re-calling of 'no-calls' using zCall for patients and controls simultaneously. Single variant and gene-based analyses were performed to identify statistically significant associations, applying Bonferroni correction. Following an extra quality control step, candidate variants were selected for validation using Sanger sequencing., Results: When we applied a MAF of ≥1.0%, no variants or genes showed statistically significant associations with ARM. Using a MAF cut-off at 0.4%, 13 variants initially reached statistical significance, but had to be discarded upon further inspection: ten variants represented calling errors of the software, while the minor alleles of the remaining three variants were not confirmed by Sanger sequencing., Conclusion: Our results show that rare and low-frequency coding variants with large effect sizes, present on the exome chip do not contribute to ARM etiology., Competing Interests: The authors have declared that no competing interests exist.

Congenital lower urinary-tract obstruction (LUTO) is caused by anatomical blockage of the bladder outflow tract or by functional impairment of urinary voiding. About three out of 10,000 pregnancies are affected. Although several monogenic causes of functional obstruction have been defined, it is unknown whether congenital LUTO caused by anatomical blockage has a monogenic cause. Exome sequencing in a family with four affected individuals with anatomical blockage of the urethra identified a rare nonsense variant (c.2557C>T [p.Arg853 ∗ ]) in BNC2, encoding basonuclin 2, tracking with LUTO over three generations. Re-sequencing BNC2 in 697 individuals with LUTO revealed three further independent missense variants in three unrelated families. In human and mouse embryogenesis, basonuclin 2 was detected in lower urinary-tract rudiments. In zebrafish embryos, bnc2 was expressed in the pronephric duct and cloaca, analogs of the mammalian lower urinary tract. Experimental knockdown of Bnc2 in zebrafish caused pronephric-outlet obstruction and cloacal dilatation, phenocopying human congenital LUTO. Collectively, these results support the conclusion that variants in BNC2 are strongly implicated in LUTO etiology as a result of anatomical blockage., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Preoperative illnesses might induce immunosuppression and subsequently increase morbidity after surgery. Several studies have tried to identify risk factors for complications after hypospadias correction, but effects of illnesses in the weeks just before surgery are unknown. We aimed to determine the associations between preoperative illnesses not severe enough to postpone surgery and short-term complications after hypospadias repair in children., Methods: In this retrospective cohort study, data were collected from 681 children with anterior or middle type hypospadias that had initial 1-stage repair in the period 1983-2012 in the Radboudumc, The Netherlands. The associations between common illnesses, such as common cold, fever and ear infection, within 2 weeks before repair, and postoperative complications, such as urethrocutaneous fistula, wound dehiscence and stenosis, within 2 months and 1 year after surgery, were analyzed using multivariable logistic regression analyses., Results: Of the 681 boys, 22% had preoperative illnesses, most often common cold, and 14% had postoperative complications. Children with preoperative illnesses had fewer postoperative complications within 2 months (n = 13, 9%) than children without preoperative illnesses (n = 79, 16%), resulting in a 50% risk reduction (odds ratio: 0.49; 95% confidence interval: 0.26-0.93). Preoperative infections (common cold, fever and ear infection), in particular, reduced the risk of postoperative infections (wound and urinary tract infections; odds ratio: 0.37; 95% confidence interval: 0.14-0.98). Results were similar for complications within 1 year., Conclusions: Common preoperative illnesses not severe enough to postpone surgery did not increase the postoperative complication risk and even seemed to have a protective effect, especially for postoperative infections. Consequently, there is no reason to alter preoperative screening.

Background: Chronic respiratory diseases and use of antiasthmatic medication during pregnancy may both play a role in the etiology of congenital anorectal malformations (ARM). However, it is unclear, whether the medication use or the underlying condition would be responsible. Therefore, our aim was to unravel the role of maternal chronic respiratory diseases from that of antiasthmatic medication in the etiology of ARM., Methods: We obtained 412 ARM patients and 2,137 population-based controls from the Dutch AGORA data- and biobank. We used maternal questionnaires and follow-up telephone interviews to obtain information on chronic respiratory diseases, antiasthmatic medication use, and potential confounders. Multivariable logistic regression analyses were performed to estimate odds ratios (ORs) with 95% confidence intervals (95% CI)., Results: We observed higher risk estimates among women with chronic respiratory diseases with and without medication use (1.4 [0.8-2.7] and 2.0 [0.8-5.0]), both in comparison to women without a chronic respiratory disease and without medication use. Furthermore, increased ORs of ARM were found for women using rescue medication (2.4 [0.8-7.3]) or a combination of maintenance and rescue medication (2.5 [0.9-6.7]). In addition, increased risk estimates were observed for women having nonallergic triggers (2.5 [1.0-6.3]) or experiencing exacerbations during the periconceptional period (3.5 [1.4-8.6])., Conclusions: Although the 95% CIs of most associations include the null value, the risk estimates all point towards an association between uncontrolled chronic respiratory disease, instead of antiasthmatic medication use, with ARM in offspring. Further in-depth studies towards mechanisms of this newly identified risk factor are warranted., (© 2018 The Authors. Birth Defects Research published by Wiley Periodicals, Inc.)

Background: Nephronophthisis is an autosomal recessive ciliopathy and important cause of end-stage renal disease (ESRD) in children and young adults. Diagnostic delay is frequent. This study investigates clinical characteristics, initial symptoms, and genetic defects in a cohort with nephronophthisis-related ciliopathy, to improve early detection and genetic counseling., Methods: Forty patients from 36 families with nephronophthisis-related ciliopathy were recruited at university medical centers and online. Comprehensive clinical and genotypic data were recorded. Patients without molecular diagnosis were offered genetic analysis., Results: Of 40 patients, 45% had isolated nephronophthisis, 48% syndromic diagnosis, and 7% nephronophthisis with extrarenal features not constituting a recognizable syndrome. Patients developed ESRD at median 13 years (range 5-47). Median age of symptom onset was 9 years in both isolated and syndromic forms (range 5-26 vs. 5-33). Common presenting symptoms were fatigue (42%), polydipsia/polyuria (33%), and hypertension (21%). Renal ultrasound showed small-to-normal-sized kidneys, increased echogenicity (65%), cysts (43%), and abnormal corticomedullary differentiation (32%). Renal biopsies in eight patients showed nonspecific signs of chronic kidney disease (CKD). Twenty-three patients (58%) had genetic diagnosis upon inclusion. Thirteen of those without a genetic diagnosis gave consent for genetic testing, and a cause was identified in five (38%)., Conclusions: Nephronophthisis is genetically and phenotypically heterogeneous and should be considered in children and young adults presenting with persistent fatigue and polyuria, and in all patients with unexplained CKD. As symptom onset can occur into adulthood, presymptomatic monitoring of kidney function in syndromic ciliopathy patients should continue until at least age 30.

Introduction: Current guidelines for clinical biobanking have a strong focus on obtaining, handling, and storage of biospecimens. However, to allow for research tying biomarker analysis to clinical decision making, there should be more focus on collection of data on donor characteristics. Therefore, our aim was to develop a stepwise procedure to define a framework as a tool to help start the data collection process in clinical biobanking., Materials and Methods: The Radboud Biobank (RB) is a central clinical biobanking facility designed in accordance with the standards set by the Parelsnoer Institute, a Dutch national biobank originally initiated with eight different disease cohorts. To organize the information of these cohorts, we used our experience and knowledge in the field of biobanking and translational research to identify research domains and information categories to classify data. We extended this classification system to a stepwise procedure for defining a data collection framework and examined its utility for existing RB biobanks., Results: Our approach resulted in the definition of a three-step procedure: (1) Identification of research domains and relevant questions within the field that may benefit from biobank samples. (2) Identification of information categories and accompanying subcategories that are relevant for answering questions in identified research domains. (3) Reduction to an efficient framework based on essentiality and quality criteria. We showed the utility of the procedure for three existing RB biobanks., Discussion: We developed guidelines for the definition of a framework that supports the standardization of the biobank data collection process. Connecting the biobank database to pertinent information collected from the electronic health record will improve data quality and efficiency for both care and research. This is crucial when using the corresponding biospecimens for scientific research. Further, it also facilitates the combination of different clinical biobanks for a specific disease.