Prevalence and risk of Down syndrome in monozygotic and dizygotic multiple pregnancies in Europe: implications for prenatal screening.

OBJECTIVE: To determine risk of Down syndrome (DS) in multiple relative to singleton pregnancies, and compare prenatal diagnosis rates and pregnancy outcome. DESIGN: Population-based prevalence study based on EUROCAT congenital anomaly registries. SETTING: Eight European countries. POPULATION: 14.8 million births 1990-2009; 2.89% multiple births. METHODS: DS cases included livebirths, fetal deaths from 20 weeks, and terminations of pregnancy for fetal anomaly (TOPFA). Zygosity is inferred from like/unlike sex for birth denominators, and from concordance for DS cases. MAIN OUTCOME MEASURES: Relative risk (RR) of DS per fetus/baby from multiple versus singleton pregnancies and per pregnancy in monozygotic/dizygotic versus singleton pregnancies. Proportion of prenatally diagnosed and pregnancy outcome. STATISTICAL ANALYSIS: Poisson and logistic regression stratified for maternal age, country and time. RESULTS: Overall, the adjusted (adj) RR of DS for fetus/babies from multiple versus singleton pregnancies was 0.58 (95% CI 0.53-0.62), similar for all maternal ages except for mothers over 44, for whom it was considerably lower. In 8.7% of twin pairs affected by DS, both co-twins were diagnosed with the condition. The adjRR of DS for monozygotic versus singleton pregnancies was 0.34 (95% CI 0.25-0.44) and for dizygotic versus singleton pregnancies 1.34 (95% CI 1.23-1.46). DS fetuses from multiple births were less likely to be prenatally diagnosed than singletons (adjOR 0.62 [95% CI 0.50-0.78]) and following diagnosis less likely to be TOPFA (adjOR 0.40 [95% CI 0.27-0.59]). CONCLUSIONS: The risk of DS per fetus/baby is lower in multiple than singleton pregnancies. These estimates can be used for genetic counselling and prenatal screening

Exploring Research Priorities of Parents Who Have Children With Down Syndrome, Cleft Lip With or Without Cleft Palate, Congenital Heart Defects, and Spina Bifida Using ConnectEpeople:A Social Media Coproduction Research Study

Background: Using social media for research purposes is novel and challenging in terms of recruitment, participant knowledge about the research process, and ethical issues. This paper provides insight into the recruitment of European parents of children with specific congenital anomalies to engage in coproduction research by using social media. Secret Facebook groups, providing optimal security, were set up for newly recruited research-aware parents (RAPs) to communicate privately and confidentially with each other and for the research team to generate questions and to interpret findings. Objective: This study aimed to use social media for the recruitment and engagement of parents in research and to determine the research priorities of parents who have children with Down syndrome, cleft lip with or without cleft palate, congenital heart defects, and spina bifida. Methods: The design was exploratory and descriptive with 3 phases. Phase 1 included the recruitment of RAPs and generation of research questions important to them; phase 2 was a Web-based survey, designed using Qualtrics software, and phase 3 included analysis and ranking of the top 10 research questions using an adapted James Lind Alliance approach. Simple descriptive statistics were used for analysis, and ethical approval was obtained from the Ethics Filter Committee of the Institute of Nursing and Health Research, Ulster University. Results: The recruitment of 32 RAPs was a sensitive process, varying in the time taken to consent (mean 51 days). However, parents valued the screening approach using the State-Trait Anxiety Inventory as a measure to ensure their well-being (mean 32.5). In phase 1, RAPs generated 98 research questions. In phase 2, 251 respondents accessed the Web-based survey, 248 consented, and 80 completed the survey, giving a completeness rate of 32.3% (80/248). Most parents used social media (74/80, 92%). Social media, online forums, and meeting in person were ranked the most preferable methods for communication with support groups networks and charities. Most respondents stated that they had a good understanding of research reports (71/80, 89%) and statistics (68/80, 85%) and could differentiate among the different types of research methodologies (62/80, 78%). Phase 3 demonstrated consensus among RAPs and survey respondents, with a need to know the facts about their child's condition, future health, and psychosocial and educational outcomes for children with similar issues. Conclusions: Social media is a valuable facilitator in the coproduction of research between parents and researchers. From a theoretical perspective, ocularcentrism can be an applicable frame of reference for understanding how people favor visual contact.This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement number 733001.info:eu-repo/semantics/publishedVersio

Osteopoikilosis and multiple exostoses caused by novel mutations in LEMD3 and EXT1 genes respectively - coincidence within one family

<p>Abstract</p> <p>Background</p> <p>Osteopoikilosis is a rare autosomal dominant genetic disorder, characterised by the occurrence of the hyperostotic spots preferentially localized in the epiphyses and metaphyses of the long bones, and in the carpal and tarsal bones <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. Heterozygous <it>LEMD3 </it>gene mutations were shown to be the primary cause of the disease <abbrgrp><abbr bid="B2">2</abbr></abbrgrp>. Association of the primarily asymptomatic osteopokilosis with connective tissue nevi of the skin is categorized as Buschke-Ollendorff syndrome (BOS) <abbrgrp><abbr bid="B3">3</abbr></abbrgrp>. Additionally, osteopoikilosis can coincide with melorheostosis (MRO), a more severe bone disease characterised by the ectopic bone formation on the periosteal and endosteal surface of the long bones <abbrgrp><abbr bid="B4">4</abbr><abbr bid="B5">5</abbr><abbr bid="B6">6</abbr></abbrgrp>. However, not all MRO affected individuals carry germ-line <it>LEMD3 </it>mutations <abbrgrp><abbr bid="B7">7</abbr></abbrgrp>. Thus, the genetic cause of MRO remains unknown. Here we describe a familial case of osteopoikilosis in which a novel heterozygous <it>LEMD3 </it>mutation coincides with a novel mutation in <it>EXT1</it>, a gene involved in aetiology of multiple exostosis syndrome. The patients affected with both <it>LEMD3 </it>and <it>EXT1 </it>gene mutations displayed typical features of the osteopoikilosis. There were no additional skeletal manifestations detected however, various non-skeletal pathologies coincided in this group.</p> <p>Methods</p> <p>We investigated <it>LEMD3 </it>and <it>EXT1 </it>in the three-generation family from Poland, with 5 patients affected with osteopoikilosis and one child affected with multiple exostoses.</p> <p>Results</p> <p>We found a novel c.2203C > T (p.R735X) mutation in exon 9 of <it>LEMD3</it>, resulting in a premature stop codon at amino acid position 735. The mutation co-segregates with the osteopoikilosis phenotype and was not found in 200 ethnically matched controls. Another new substitution G > A was found in <it>EXT1 </it>gene at position 1732 (cDNA) in Exon 9 (p.A578T) in three out of five osteopoikilosis affected family members. Evolutionary conservation of the affected amino acid suggested possible functional relevance, however no additional skeletal manifestations were observed other then those specific for osteopoikilosis. Finally in one member of the family we found a splice site mutation in the <it>EXT1 </it>gene intron 5 (IVS5-2 A > G) resulting in the deletion of 9 bp of cDNA encoding three evolutionarily conserved amino acid residues. This child patient suffered from a severe form of exostoses, thus a causal relationship can be postulated.</p> <p>Conclusions</p> <p>We identified a new mutation in <it>LEMD3 </it>gene, accounting for the familial case of osteopoikilosis. In the same family we identified two novel <it>EXT1 </it>gene mutations. One of them A598T co-incided with the <it>LEMD3 </it>mutation. Co-incidence of <it>LEMD3 </it>and <it>EXT1 </it>gene mutations was not associated with a more severe skeletal phenotype in those patients.</p

Integration of Hi-C with short and long-read genome sequencing reveals the structure of germline rearranged genomes

Structural variants are a common cause of disease and contribute to a large extent to inter-individual variability, but their detection and interpretation remain a challenge. Here, we investigate 11 individuals with complex genomic rearrangements including germline chromothripsis by combining short- and long-read genome sequencing (GS) with Hi-C. Large-scale genomic rearrangements are identified in Hi-C interaction maps, allowing for an independent assessment of breakpoint calls derived from the GS methods, resulting in >300 genomic junctions. Based on a comprehensive breakpoint detection and Hi-C, we achieve a reconstruction of whole rearranged chromosomes. Integrating information on the three-dimensional organization of chromatin, we observe that breakpoints occur more frequently than expected in lamina-associated domains (LADs) and that a majority reshuffle topologically associating domains (TADs). By applying phased RNA-seq, we observe an enrichment of genes showing allelic imbalanced expression (AIG) within 100 kb around the breakpoints. Interestingly, the AIGs hit by a breakpoint (19/22) display both up- and downregulation, thereby suggesting different mechanisms at play, such as gene disruption and rearrangements of regulatory information. However, the majority of interpretable genes located 200 kb around a breakpoint do not show significant expression changes. Thus, there is an overall robustness in the genome towards large-scale chromosome rearrangements

Information needs of parents of children with congenital anomalies across Europe: a EUROlinkCAT survey.

BACKGROUND: Parents of children who have a congenital anomaly can experience significant worry about their child's health. Access to clear, helpful, and trustworthy information can provide a valuable source of support. In this study the aim was to explore the information needs of parents/carers of children with congenital anomalies across Europe. METHOD: A cross-sectional online survey was developed in nine languages to measure parents' information needs, including: (1) the 'helpfulness'/'trustworthiness' of information received from eight relevant sources, and (2) overall satisfaction with information received. Parents/carers of children (0-10 years) with cleft lip, spina bifida, congenital heart defect [CHD] requiring surgery, and/or Down syndrome were recruited online via relevant organisations in 10 European countries from March-July 2021. Quantitative analyses using multivariable logistic regressions were performed. RESULTS: One thousand seventy parents/carers of children with a cleft lip (n = 247), spina bifida (n = 118), CHD (n = 366), Down syndrome (n = 281), and Down syndrome with CHD (n = 58) were recruited in Poland (n = 476), the UK (n = 120), Germany (n = 97), the Netherlands/Belgium (n = 74), Croatia (n = 68), Italy (n = 59), other European countries (n = 92), and not specified/non-European countries (n = 84). Most participants were mothers (92%) and aged 31-40 years (71%). Participants were most likely to rate support groups (63%), patient organisations (60%), specialist doctors/nurses (58%), and social media (57%) as 'very helpful' information sources. 'Very trustworthy' ratings remained high for specialist doctors/nurses (61%), however, they declined for support groups (47%), patient organisations (48%), and social media (35%). Germany had the highest proportion of participants who were 'very satisfied' (44%, 95% CI = 34%-54%) with information, whereas this percentage was lowest in Croatia (11%, 95% CI = 3%-19%) and Poland (15%, 95% CI = 11%-18%). Parents of children with Down syndrome had significantly lower satisfaction ratings than parents of children with CHD; 13% (95% CI = 8%-18%) reported being 'very satisfied' compared to 28% (95% CI = 23%-33%) in the CHD group. CONCLUSIONS: Findings suggest that informal sources of information (e.g. support groups) are of value to parents, however, they are not deemed as trustworthy as specialist medical sources. Satisfaction ratings differed across countries and by anomaly, and were particularly low in Croatia and Poland, as well as for parents of children with Down syndrome, which warrants further investigation

Integration of Hi-C with short and long-read genome sequencing reveals the structure of germline rearranged genomes

Here the authors characterize structural variations (SVs) in a cohort of individuals with complex genomic rearrangements, identifying breakpoints by employing short- and long-read genome sequencing and investigate their impact on gene expression and the three-dimensional chromatin architecture. They find breakpoints are enriched in inactive regions and can result in chromatin domain fusions.Structural variants are a common cause of disease and contribute to a large extent to inter-individual variability, but their detection and interpretation remain a challenge. Here, we investigate 11 individuals with complex genomic rearrangements including germline chromothripsis by combining short- and long-read genome sequencing (GS) with Hi-C. Large-scale genomic rearrangements are identified in Hi-C interaction maps, allowing for an independent assessment of breakpoint calls derived from the GS methods, resulting in &gt;300 genomic junctions. Based on a comprehensive breakpoint detection and Hi-C, we achieve a reconstruction of whole rearranged chromosomes. Integrating information on the three-dimensional organization of chromatin, we observe that breakpoints occur more frequently than expected in lamina-associated domains (LADs) and that a majority reshuffle topologically associating domains (TADs). By applying phased RNA-seq, we observe an enrichment of genes showing allelic imbalanced expression (AIG) within 100 kb around the breakpoints. Interestingly, the AIGs hit by a breakpoint (19/22) display both up- and downregulation, thereby suggesting different mechanisms at play, such as gene disruption and rearrangements of regulatory information. However, the majority of interpretable genes located 200 kb around a breakpoint do not show significant expression changes. Thus, there is an overall robustness in the genome towards large-scale chromosome rearrangements

Mutations in DSTYK and dominant urinary tract malformations.

ABSTRACT Introduction Congenital abnormalities of the kidney of the urinary tract are the most common cause of pediatric kidney failure. These disorders are highly heterogeneous, and their etiology is poorly understood. Methods We performed genome-wide linkage analysis and whole-exome sequencing in a family with autosomal dominant congenital abnormalities of the kidney of the urinary tract (7 affected family members). We also performed sequence analysis in 311 unrelated patients, as well as histologic and functional studies. Results Linkage analysis identified five regions of the genome that were shared among all affected family members. Exome sequencing identified a single rare deleterious variant within these linkage intervals, a heterozygous splice-site mutation in dual serine/threonine and tyrosine protein kinase (DSTYK). This variant, which resulted in aberrant gene product splicing, was present in all affected family members. Additional independent DSTYK mutations, including nonsense and splice-site mutations, were detected among 7/311 unrelated patients. DSTYK is highly expressed in the maturing epithelia of all major organs, localizing to cell membranes. Knockdown in zebrafish resulted in multi-organ developmental defects, resembling loss of fibroblast growth factor (FGF) signaling. Consistent with this finding, DSTYK colocalizes with FGF receptors in the ureteric bud and metanephric mesenchyme. Finally, DSTYK knockdown in human embryonic kidney cells inhibited FGF-stimulated ERK-phosphorylation, the principal signal downstream of receptor tyrosine kinases. Conclusions We detected DSTYK mutations in 2.2% of patients with congenital abnormalities of the kidney and urinary tract whom we studied, suggesting that DSTYK is a major determinant of human urinary tract development, downstream of FGF signaling

Amniotic band syndrome and limb body wall complex in Europe 1980–2019

Amniotic band syndrome (ABS) and limb body wall complex (LBWC) have an overlapping phenotype of multiple congenital anomalies and their etiology is unknown. We aimed to determine the prevalence of ABS and LBWC in Europe from 1980 to 2019 and to describe the spectrum of congenital anomalies. In addition, we investigated maternal age and multiple birth as possible risk factors for the occurrence of ABS and LBWC. We used data from the European surveillance of congenital anomalies (EUROCAT) network including data from 30 registries over 1980–2019. We included all pregnancy outcomes, including live births, stillbirths, and terminations of pregnancy for fetal anomalies. ABS and LBWC cases were extracted from the central EUROCAT database using coding information responses from the registries. In total, 866 ABS cases and 451 LBWC cases were included in this study. The mean prevalence was 0.53/10,000 births for ABS and 0.34/10,000 births for LBWC during the 40 years. Prevalence of both ABS and LBWC was lower in the 1980s and higher in the United Kingdom. Limb anomalies and neural tube defects were commonly seen in ABS, whereas in LBWC abdominal and thoracic wall defects and limb anomalies were most prevalent. Twinning was confirmed as a risk factor for both ABS and LBWC. This study includes the largest cohort of ABS and LBWC cases ever reported over a large time period using standardized EUROCAT data. Prevalence, clinical characteristics, and the phenotypic spectrum are described, and twinning is confirmed as a risk factor.publishedVersio