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The underrepresentation of non-European ancestry groups in current genomic databases complicates interpretation of their genetic test results, yielding a much higher prevalence of variants of uncertain significance (VUSs). Such VUS findings can frustrate the goals of genetic testing, create anxiety in patients, and lead to unnecessary medical interventions. Approaches to addressing underrepresentation of people with genetic ancestries other than European are being undertaken by broad-based recruitment efforts. However, some underrepresented groups have concerns that might preclude participation in such efforts. We describe here two initiatives aimed at meeting the needs of underrepresented ancestry groups in genomic datasets. The two communities, the Sephardi Jewish community in New York and First Peoples of Canada, have very different concerns about contributing to genomic research and datasets. Sephardi concerns focus on the possible negative effects of genetic findings on the marriage prospects of family members. Canadian Indigenous populations seek control over the research uses to which their genetic data would be put. Both cases involve targeted efforts to respond to the groups’ concerns; these efforts include governance models aimed at ensuring that the data are used primarily to inform clinical test analyses and at achieving successful engagement and participation of community members. We suggest that these initiatives could provide models for other ancestral groups seeking to improve the accuracy and utility of clinical genetic testing while respecting the underlying preferences and values of community members with regard to the use of their genetic data.

Inherited arrhythmia conditions (IAC) can lead to sudden cardiac death at any age, and relatives of an affected person have up to a 50% chance of inheriting the condition and are at risk for developing features. Cascade testing is a stepwise approach for identifying relatives at risk for IACs through clinical screening and genetic testing. Early detection can reduce morbidity and mortality for affected individuals and determine potential risk mitigation strategies for relatives. However, cardiovascular genetic studies have reported an incomplete uptake of cascade testing in at-risk relatives. We explored patient perspectives on cascade testing for IACs and alternative approaches to family communication. Twelve semi-structured phone interviews were conducted with probands of the British Columbia Inherited Arrhythmia Program confirmed to carry a pathogenic or likely pathogenic variant in a gene associated with an IAC. Thematic analysis of transcripts through an iterative coding process revealed five main themes: (a) a stepwise approach is followed in disclosing risk to relatives, (b) relatives' autonomy in cascade testing is supported, (c) lived experience with the condition influences disclosure and uptake of cascade testing, (d) collaborative approach to informing relatives reduces negative impact of disclosure, and (e) direct contact from a healthcare provider is viewed as acceptable. The findings highlight this patient cohort's experiences and opinions with approaches to disclosure and demonstrate their understanding and acceptance of their relatives' approaches to cascade testing. In addition, while the notion of direct contact was generally accepted, a collaborative approach to contacting relatives between the proband and provider may be most effective.

Background: Congenital anomalies (CA) are one of the leading causes of infant mortality and long-term disability. Many jurisdictions rely on health administrative data to monitor these conditions. Case definition algorithms can be used to monitor CA; however, validation of these algorithms is needed to understand the strengths and limitations of the data. This study aimed to validate case definition algorithms used in a CA surveillance system in British Columbia (BC), Canada. Methods: A cohort of births between March 2000 and April 2002 in BC was linked to the Health Status Registry (HSR) and the BC Congenital Anomalies Surveillance System (BCCASS) to identify cases and non-cases of specific anomalies within each surveillance system. Measures of algorithm performance were calculated for each CA using the HSR as the reference standard. Agreement between both databases was calculated using kappa coefficient. The modified Standards for Reporting Diagnostic Accuracy guidelines were used to enhance the quality of the study. Results: Measures of algorithm performance varied by condition. Positive predictive value (PPV) ranged between approximately 73%–100%. Sensitivity was lower than PPV for most conditions. Internal congenital anomalies or conditions not easily identifiable at birth had the lowest sensitivity. Specificity and negative predictive value exceeded 99% for all algorithms. Conclusion: Case definition algorithms may be used to monitor CA at the population level. Accuracy of algorithms is higher for conditions that are easily identified at birth. Jurisdictions with similar administrative data may benefit from using validated case definitions for CA surveillance as this facilitates cross-jurisdictional comparison.

To determine the long-term risk of mortality among children with inborn errors of metabolism.We conducted a retrospective cohort study of 1750 children with inborn errors of metabolism (excluding mitochondrial disorders) and 1 036 668 children without errors of metabolism who were born in Quebec, Canada, between 2006 and 2019. Main outcome measures included all-cause and cause-specific mortality between birth and 14 years of age. We used adjusted survival regression models to estimate HRs and 95% CIs for the association between inborn errors of metabolism and mortality over time.Mortality rates were greater for children with errors of metabolism than for unaffected children (69.1 vs 3.2 deaths per 10 000 person-years). During 7 702 179 person-years of follow-up, inborn errors of metabolism were associated with 21.2 times the risk of mortality compared with no error of metabolism (95% CI 17.23-26.11). Disorders of mineral metabolism were associated with greater mortality the first 28 days of life (HR 60.62, 95% CI 10.04-365.98), and disorders of sphingolipid metabolism were associated with greater mortality by 1 year (HR 284.73, 95% CI 139.20-582.44) and 14 years (HR 1066.00, 95% CI 298.91-3801.63). Errors of metabolism were disproportionately associated with death from hepatic/digestive (HR 208.21, 95% CI 90.28-480.22), respiratory (HR 116.57, 95% CI 71.06-191.23), and infectious causes (HR 119.83, 95% CI 40.56-354.04).Children with errors of metabolism have a considerably elevated risk of mortality before 14 years, including death from hepatic/digestive, respiratory, and infectious causes. Targeting these causes of death may help improve long-term survival.

Background: The Hearts in Rhythm Organization (HiRO) is a team of Canadian inherited heart rhythm and cardiomyopathy experts, genetic counsellors, nurses, researchers, patients, and families dedicated to the detection of inherited arrhythmias and cardiomyopathies, provision of best therapies, and protection from the tragedy of sudden cardiac arrest. Methods: Recently, existing disease-specific registries were merged into the expanded National HiRO Registry, creating a single common data set for patients and families with inherited conditions that put them at risk for sudden death in Canada. Eligible patients are invited to participate in the registry and optional biobank from 20 specialized cardiogenetics clinics across Canada. Results: Currently, there are 4700 participants enrolled in the National HiRO Registry, with an average of 593 participants enrolled annually over the past 5 years. The capacity to enable knowledge translation of research findings is built into HiRO’s organizational infrastructure, with 3 additional working groups (HiRO Clinical Care Committee, HiRO Active Communities Committee, and HiRO Annual Symposium Committee), supporting the organization’s current goals and priorities as set alongside patient partners. Conclusion: The National HiRO Registry aims to be an integrated research platform to which researchers can pose novel research questions leading to a better understanding, detection, and clinical care of those living with inherited heart rhythm and cardiomyopathy conditions and ultimately to prevent sudden cardiac death. Résumé: Contexte: La Hearts in Rhythm Organization (HiRO) est une équipe d’experts canadiens en matière de rythmes cardiaques et de cardiomyopathies héréditaires, de conseillers en génétique, d’infirmières, de chercheurs, de patients et de familles qui se consacrent à la détection des arythmies et des cardiomyopathies héréditaires, à la mise en place des meilleures thérapies et à la protection contre la tragédie que représente une mort subite d’origine cardiaque. Méthodes: Récemment, les registres existants relatifs à des maladies spécifiques ont été fusionnés en un registre national élargi de l’HiRO, créant ainsi un ensemble de données commun unique à destination des patients et leurs familles, atteints de maladies héréditaires, qui sont à risque de mort subite au Canada. Les patients admissibles sont invités à s’associer au registre et à la biobanque facultative regroupant 20 cliniques spécialisées en cardiogénétique au Canada. Résultats: Actuellement, 4 700 participants sont inscrits au registre national de l’HiRO, avec une moyenne de 593 participants inscrits chaque année au cours des cinq dernières années. La capacité à favoriser l’application des connaissances issues de la recherche fait partie de la structure organisationnelle de l’HiRO, avec trois groupes de travail supplémentaires (comité des soins cliniques de l’HiRO, comité des communautés cctives de l’HiRO et comité du symposium annuel de l’HiRO), soutenant les objectifs et les priorités actuels de l’organisation tels qu’ils ont été fixés en partenariat avec les patients. Conclusion: Le registre national de l’HiRO vise à devenir une plateforme de recherche intégrée au sein de laquelle les chercheurs peuvent exposer des questions de recherche inédites permettant de mieux comprendre, détecter et soigner les personnes atteintes de troubles du rythme cardiaque et de cardiomyopathie héréditaires et, à terme, de prévenir la mort subite d’origine cardiaque.

There is a disproportionately high rate of hereditary long QT syndrome (LQTS) in Northern British Columbia First Nations people, largely due to a novel missense variant in KCNQ1 (p.V205M). The variant has been previously described predisposing those affected to syncope, arrhythmia, and sudden death. Although the biological aspects of LQTS have been explored extensively, less research has been done into the impact of living with a genetic variant that predisposes one to sudden death, and no previous studies have provided cultural insights from a First Nations community. The goal of this study was to explore what facilitates and hinders resiliency and coping for those living with LQTS. Participants were invited to partake in their choice of one-to-one interviews, Photovoice, and Talking Circles. This paper presents the findings from the interview portion of the study. Interviews were recorded, transcribed, and analyzed qualitatively using the systematic text condensation method. Ten women shared their personal experiences of living with LQTS through individual interviews. Half of the women had tested positive for the p.V205M variant, and the other half were awaiting results. In general, learning about a LQTS diagnosis was perceived as traumatic, with gradual acceptance that led to coping. The main factors found to facilitate resiliency and coping were positive family relationships, spirituality, and knowledge about LQTS. The main factors found to hinder resiliency and coping were a poor understanding of the biological or clinical aspects of LQTS, conflicting medical advice (especially regarding physical activity) and LQTS not being taken seriously by social contacts and healthcare providers. It appears that learning to live with LQTS is an ongoing process, requiring balance and interconnectedness between all aspects of well-being.

Addressing Indigenous rights and interests in genetic resources has become increasingly challenging in an open science environment that promotes unrestricted access to genomic data. Although Indigenous experiences with genetic research have been shaped by a series of negative interactions, there is increasing recognition that equitable benefits can only be realized through greater participation of Indigenous communities. Issues of trust, accountability and equity underpin Indigenous critiques of genetic research and the sharing of genomic data. This Perspectives article highlights identified issues for Indigenous communities around the sharing of genomic data and suggests principles and actions that genomic researchers can adopt to recognize community rights and interests in data.

Ankyrin-B (AnkB) is scaffolding protein that anchors integral membrane proteins to the cardiomyocyte cytoskeleton. We recently identified an AnkB variant, AnkB p.S646F (ANK2 c.1937 C>T) associated with a phenotype ranging from predisposition for cardiac arrhythmia to cardiomyopathy. AnkB p.S646F exhibited reduced expression levels in the H9c2 rat ventricular-derived cardiomyoblast cell line relative to wildtype AnkB. Here, we demonstrate that AnkB is regulated by proteasomal degradation and proteasome inhibition rescues AnkB p.S646F expression levels in H9c2 cells, although this effect is not conserved with differentiation. We also compared the impact of wildtype AnkB and AnkB p.S646F on cell viability and proliferation. AnkB p.S646F expression resulted in decreased cell viability at 30 h after transfection, whereas we observed a greater proportion of cycling, Ki67-positive cells at 48 h after transfection. Notably, the number of GFP-positive cells was low and was consistent between wildtype AnkB and AnkB p.S646F expressing cells, suggesting that AnkB and AnkB p.S646F affected paracrine communication between H9c2 cells differentially. This work reveals that AnkB levels are regulated by the proteasome and that AnkB p.S646F compromises cell viability. Together, these findings provide key new insights into the putative cellular and molecular mechanisms of AnkB-related cardiac disease.

Genomic variation plays a crucial role in biology, serving as a base for evolution - allowing for adaptation on a species or population level. At the individual level, however, specific alleles can be implicated in diseases. To interpret genetic variants identified in an individual potentially affected with a rare genetic disease, it is fundamental to know the population frequency of each allele, ideally in an ancestry matched cohort. Equity in human genomics remains a challenge for the field, and there are not yet cohorts representing most populations. Currently, when ancestry matched cohorts are not available, pooled variant libraries are used, such as gnomAD, the Human Genome Diversity Project (HGDP) or the 1,000 Genomes Project (now known as IGSR: International Genome Sample Resource). When working with a pooled collection of variant frequencies, one of the challenges is to determine efficiently if a variant is broadly spread across populations or appears selectively in one or more populations. While this can be accomplished by reviewing tables of population frequencies, it can be advantageous to have a single score that summarizes the observed dispersion. This score would not require classifying individuals into populations, which can be complicated if it is a homogenous population, or can leave individuals excluded from all the predefined population groups. Moreover, a score would not display fine-scaled population information, which could have privacy implications and consequently be inappropriate to release. Therefore, we sought to develop a scoring method based on a Uniform Manifold Approximation and Projection (UMAP) where, for each allele, the score can range from 0 (the variant is limited to a subset of close individuals within the whole cohort) to 1 (the variant is spread among the individuals represented in the cohort). We call this score the Allele Dispersion Score (ADS). The scoring system was implemented on the IGSR dataset, and compared to the current method consisting in displaying variant frequencies for several populations in a table. The ADS correlates with the population frequencies, without requiring grouping of individuals.

Congenital anomalies (CAs) can cause lifelong morbidity and accounted for 23.2% of infant deaths from 2003 to 2007. In British Columbia (BC), surveillance of CAs has been irregular since the early 2000s. To enhance CAs surveillance in BC, the Public Health Agency of Canada has provided funding for the implementation of the BC Congenital Anomalies Surveillance System (BCCASS).BCCASS is a population-based surveillance system. The system leverages existing administrative data sources that capture information regarding vital events, disease status, drug prescription, and healthcare utilization. The system uses a series of algorithms to capture specific CAs diagnoses, some of which are further validated with the support of the Provincial Advisory Committee. This Advisory Committee is a multi-stakeholder coalition that includes the BC Office of the Provincial Health Officer, subject matter experts, data partners, users, and academia, and acts to provide support, expertise, and strategic guidance to BCCASS.Through BCCASS, prevalence and historical trends for 35 CAs in BC are available. Information pertaining to maternal place of residence, risk, and protective factors can be used for association studies such as links to environmental hazards and cluster analysis.BCCASS is a cost-effective and sustainable system that leverages existing data sources necessary to understand the overall burden of CAs across the BC population. This is fundamental to support data-driven decisions around policy development, program planning, and evaluation of preventive measures. Strong coalitions with stakeholders are instrumental to ensure successful implementation and expansion in the future.RéSUME: CONTEXTE: Les anomalies congénitales (AC) peuvent causer une morbidité à vie et ont représenté 23,2 % des décès infantiles de 2003 à 2007. En Colombie-Britannique, la surveillance des AC a été irrégulière depuis le début des années 2000. Afin d’améliorer la surveillance de l’AC en Colombie-Britannique, l’Agence de la santé publique du Canada a financé la mise en œuvre du BC Congenital Anomalies Surveillance System (BCCASS). INTERVENTION: Le BCCASS est un système de surveillance basé sur la population. Le système exploite les sources de données administratives existantes qui capturent des informations concernant les événements vitaux, les diagnostics médicaux, la prescription de médicaments et l’utilisation des soins de santé. Le système utilise une série d’algorithmes pour saisir des diagnostics d’AC spécifiques, dont certains sont ensuite validés avec le soutien du Comité consultatif provincial. Ce comité consultatif est une coalition multipartite entre le bureau de l’Agence de santé provincial de la Colombie-Britannique, des experts en la matière, des partenaires de données, des utilisateurs et des universitaires, qui agit pour fournir un soutien, une expertise et des conseils stratégiques au BCCASS. RéSULTATS: Par le BCCASS, la prévalence et les tendances historiques pour 35 AC en Colombie-Britannique sont disponibles. Les informations relatives au lieu de résidence de la mère, aux facteurs de risque et de protection peuvent être utilisées pour des études d’association telles que les liens avec les facteurs environnementaux et l’analyse typologique. INCIDENCES: Le BCCASS est un système rentable et durable qui tire parti des sources de données existantes nécessaires pour comprendre le fardeau global des CA dans l’ensemble de la population de la Colombie-Britannique. Ceci est fondamental pour soutenir les décisions fondées sur les données concernant l’élaboration de politiques, la planification de programmes et l’évaluation des mesures préventives. Des coalitions solides avec les parties prenantes sont essentielles pour assurer une mise en œuvre et une expansion réussie dans l’avenir.

Summary: Background: Historical, colonial, and racist policies continue to influence the health of Indigenous people, and they continue to have higher rates of chronic diseases and reduced life expectancy compared with non-Indigenous people. We determined factors accounting for variations in cardiovascular risk factors among First Nations communities in Canada. Methods: Men and women (n=1302) aged 18 years or older from eight First Nations communities participated in a population-based study. Questionnaires, physical measures, blood samples, MRI of preclinical vascular disease, and community audits were collected. In this cross-sectional analysis, the main outcome was the INTERHEART risk score, a measure of cardiovascular risk factor burden. A multivariable model was developed to explain the variations in INTERHEART risk score among communities. The secondary outcome was MRI-detected carotid wall volume, a measure of subclinical atherosclerosis. Findings: The mean INTERHEART risk score of all communities was 17·2 (SE 0·2), and more than 85% of individuals had a risk score in the moderate to high risk range. Subclinical atherosclerosis increased significantly across risk score categories (p

We examined the birth outcomes of children with inborn errors of metabolism detected at birth or later in life.We carried out a retrospective cohort study of 1733 children with inborn errors of metabolism and 1,033,693 unaffected children born in Canada between 2006 and 2019. Primary outcomes included preterm birth, low birth weight, congenital anomalies, and other neonatal complications. We estimated adjusted risk ratios (RR) and 95% confidence intervals (CI) for the association of inborn errors of metabolism with each outcome.Children with inborn errors of metabolism had 2.51 times the risk of preterm birth (95% CI 2.27-2.77) and 3.08 times the risk of low birth weight (95% CI 2.77-3.42) compared with unaffected children. Disorders of mineral and lipoprotein metabolism were more strongly associated with adverse birth outcomes. Inborn errors of metabolism were associated with congenital anomalies (RR 2.62; 95% CI 2.36-2.90), particularly abdominal wall defects (RR 8.35; 95% CI 5.18-13.44). Associations were present for errors of metabolism diagnosed both at birth and later in life.Children with inborn errors of metabolism, whether detected at birth or later, are at high risk of adverse birth outcomes and congenital anomalies.Inborn errors of metabolism may affect fetal development, but the association with adverse birth outcomes is not well characterized. This study indicates that children with inborn errors of metabolism are at risk of preterm birth, neonatal jaundice, congenital anomalies, and a range of other adverse birth outcomes. Mothers of children with inborn errors of metabolism are at risk of preeclampsia and cesarean delivery. Adverse birth outcomes may be a first sign of inborn errors of metabolism that merit increased screening.

Aims Genetic testing is recommended in specific inherited heart diseases but its role remains unclear and it is not currently recommended in unexplained cardiac arrest (UCA). We sought to assess the yield and clinical utility of genetic testing in UCA using whole-exome sequencing (WES). Methods and results Survivors of UCA requiring external defibrillation were included from the Cardiac Arrest Survivor with Preserved Ejection fraction Registry. Whole-exome sequencing was performed, followed by assessment of rare variants in previously reported cardiovascular disease genes. A total of 228 UCA survivors (mean age at arrest 39 ± 13 years) were included. The majority were males (66%) and of European ancestry (81%). Following advanced clinical testing at baseline, the likely aetiology of cardiac arrest was determined in 21/228 (9%) cases. Whole-exome sequencing identified a pathogenic or likely pathogenic (P/LP) variant in 23/228 (10%) of UCA survivors overall, increasing the proportion of ‘explained’ cases from 9% only following phenotyping to 18% when combining phenotyping with WES. Notably, 13 (57%) of the 23 P/LP variants identified were located in genes associated with cardiomyopathy, in the absence of a diagnosis of cardiomyopathy at the time of arrest. Conclusions Genetic testing identifies a disease-causing variant in 10% of apparent UCA survivors. The majority of disease-causing variants was located in cardiomyopathy-associated genes, highlighting the arrhythmogenic potential of such variants in the absence of an overt cardiomyopathy diagnosis. The present study supports the use of genetic testing including assessment of arrhythmia and cardiomyopathy genes in survivors of UCA.

Background The diagnostic journey for many rare disease patients remains challenging despite use of latest genetic technological advancements. We hypothesize that some patients remain undiagnosed due to more complex diagnostic scenarios that are currently not considered in genome analysis pipelines. To better understand this, we characterized the rare disorder (RD) spectrum using various bioinformatics resources (e.g., Orphanet/Orphadata, Human Phenotype Ontology, Reactome pathways) combined with custom-made R scripts. Results Our in silico characterization led to identification of 145 borderline-common, 412 rare and 2967 ultra-rare disorders. Based on these findings and point prevalence, we would expect that approximately 6.53%, 0.34%, and 0.30% of individuals in a randomly selected population have a borderline-common, rare, and ultra-rare disorder, respectively (equaling to 1 RD patient in 14 people). Importantly, our analyses revealed that (1) a higher proportion of borderline-common disorders were caused by multiple gene defects and/or other factors compared with the rare and ultra-rare disorders, (2) the phenotypic expressivity was more variable for the borderline-common disorders than for the rarer disorders, and (3) unique clinical characteristics were observed across the disorder categories forming the spectrum. Conclusions Recognizing that RD patients who remain unsolved even after genome sequencing might belong to the more common end of the RD spectrum support the usage of computational pipelines that account for more complex genetic and phenotypic scenarios.

Objective: Infectious illness, including lower respiratory tract infection (LRTI), is a leading cause of childhood morbidity and infant mortality in Inuit children in Nunavut Canada. The carnitine palmitoyltransferase 1A (CPT1A) p.P479L variant is common in arctic Indigenous populations of Alaska, Canada, and Greenland. CPT1A is a fatty acid oxidation enzyme expressed in the liver, immunocytes and other tissues, and is needed to use fats for energy during fasting. Previous association of the variant with early childhood infectious illness and infant death has been challenged because of sample size and limited adjustment for confounders. We evaluated whether the p.P479L variant is associated with infectious illness in Inuit children of Nunavut, Canada.Methods: We conducted a retrospective clinical chart review of 2,225 Inuit children (0–5 years) for infectious illness (including otitis media, gastroenteritis, and hospital admission for LRTI), prenatal, perinatal, and socioeconomic indicators, subsequently linking to CPT1A genotype. Multivariable logistic regression adjusted for birth characteristics, breastfeeding, maternal smoking, food insecurity, and socioeconomic indicators.Results: Overall, 27% of children were hospitalized for LRTI, 86% had otitis media and 50% had gastroenteritis. The p.P479L allele frequency was 0.82. In multivariable analysis, p.P479L homozygosity was associated with LRTI admission (aOR:2.88 95%CI:1.46–5.64), otitis media (aOR:1.83, 95%CI:1.05–3.21), and gastroenteritis (aOR:1.74, 95%CI:1.09–2.77), compared to non-carriers.Conclusion: Children homozygous for the p.P479L variant were more likely to experience infectious illness than non-carriers, including hospitalization for respiratory tract infections. Given the role of CPT1A in immunocytes, our findings indicate that more study is needed to determine if there is a role of the variant in immune response. Continued Inuit involvement is essential when considering next steps.

Research teams developing biobanks and/or genomic databases must develop policies for the disclosure and reporting of potentially actionable genomic results to research participants. Currently, a broad range of approaches to the return of results exist, with some studies opting for non-disclosure of research results while others follow clinical guidelines for the return of potentially actionable findings from sequencing. In this review, we describe current practices and highlight decisions a research team must make when designing a return of results policy, from informed consent to disclosure practices and clinical validation options. The unique challenges of returning incidental findings in cardiac genes, including reduced penetrance and the lack of clinical screening standards for phenotype-negative individuals are discussed. Lastly, the National Hearts in Rhythm Organization (HiRO) Registry approach is described to provide a rationale for the selective return of field-specific variants to those participating in disease-specific research. Our goal is to provide researchers with a resource when developing a return of results policy tailored for their research program, based on unique factors related to study design, research team composition and availability of clinical resources.

BACKGROUND Previous studies showed increases in rates of gastroschisis in Canada in the first decade of the 21st century. OBJECTIVE We sought to examine the epidemiologic characteristics of gastroschisis in Canada in recent years. METHODS We conducted a retrospective population-based cohort study of all livebirths and stillbirths delivered in Canada (excluding Quebec) from 2006 to 2017, with information obtained from the Canadian Institute for Health Information. Gastroschisis rates by maternal age, region of residence, and maternal and infant characteristics were quantified using prevalence rate ratios (RR) and 95% confidence intervals (CI). Log-binomial regression was used to quantify the associations between risk factors and gastroschisis. RESULTS There were 1314 gastroschisis cases among 3 364 116 births. The prevalence rate was 3.7 per 10 000 total births in 2006 and 3.4 per 10 000 total births in 2017, with substantial annual variation in rates. The proportion of mothers aged 20-24 years decreased from 16.5% in 2006 to 11.3% in 2017, while the proportion of mothers aged

BACKGROUND Data on the relationship between bariatric surgery and risk of birth defects are conflicting. OBJECTIVES We studied the association of bariatric surgery with birth defects in future pregnancies in a large cohort of women. METHODS We carried out a retrospective cohort study of 2,194,348 pregnancies that occurred between 1989 and 2016 in Quebec, Canada. We identified women who had bariatric surgery before pregnancy, and included nonobese women with no surgery as a comparison group. We estimated risk ratios (RRs) and 95% CIs for the associations between bariatric surgery and the risk of birth defects, using log-binomial regression models adjusted for maternal age, comorbidities, parity, whether there was a multiple birth, socioeconomic deprivation, and the presence of folic acid food fortification. RESULTS In this study, 1845 deliveries were among women who had bariatric surgery before pregnancy (0.08%). Having bariatric surgery was associated with 1.20 times the risk of birth defects in later pregnancies (95% CI: 1.01, 1.43), compared with having no surgery or obesity. Obesity without having bariatric surgery was, in contrast, more weakly associated with birth defects (RR: 1.09; 95% CI: 1.07, 1.12). The association with bariatric surgery was greater for heart (RR: 1.47; 95% CI: 1.02, 2.12) and musculoskeletal defects (RR: 1.32; 95% CI: 1.02, 1.71). Associations were primarily present before folic acid food fortification was implemented (RR: 2.03; 95% CI: 1.41, 2.92), but not after (RR: 1.05; 95% CI: 0.86, 1.28). CONCLUSIONS Having bariatric surgery was a risk factor for birth defects, and particularly heart and musculoskeletal defects. After fortification, however, an association was no longer present. Future studies are needed to determine whether micronutrient supplementation underpins the difference in the changing results pre- and postfortification.

Background There is no international consensus on the definition and components of severe maternal morbidity (SMM). Objectives To propose a comprehensive definition of SMM, to create an empirically justified list of SMM types and subtypes, and to use this to examine SMM in Canada. Methods Severe maternal morbidity was defined as a set of heterogeneous maternal conditions known to be associated with severe illness and with prolonged hospitalisation or high case fatality. Candidate SMM types/subtypes were evaluated using information on all hospital deliveries in Canada (excluding Quebec), 2006‐2015. SMM rates for 2012‐2016 were quantified as a composite and as SMM types/subtypes. Rate ratios and population attributable fractions (PAF) associated with overall and specific SMM types/subtypes were estimated in relation to length of hospital stay (LOS > 7 days) and case fatality. Results There were 22 799 cases of SMM subtypes (among 1 418 545 deliveries) that were associated with a prolonged LOS or high case fatality. Between 2012 and 2016, the composite SMM rate was 16.1 (95% confidence interval [CI] 15.9, 16.3) per 1000 deliveries. Severe pre‐eclampsia and HELLP syndrome (514.6 per 100 000 deliveries), and severe postpartum haemorrhage (433.2 per 100 000 deliveries) were the most common SMM types, while case fatality rates among SMM subtypes were highest among women who had cardiac arrest and resuscitation (241.1 per 1000), hepatic failure (147.1 per 1000), dialysis (67.6 per 1000), and cerebrovascular accident/stroke (51.0 per 1000). The PAF for prolonged hospital stay related to SMM was 17.8% (95% CI 17.3, 18.3), while the PAF for maternal death associated with SMM was 88.0% (95% CI 74.6, 94.4). Conclusions The proposed definition of SMM and associated list of SMM subtypes could be used for standardised SMM surveillance, with rate ratios and PAFs associated with specific SMM types/subtypes serving to inform clinical practice and public health policy.

Causes of birth defects are unclear, and the association with electromagnetic fields is inconclusive. We assessed the relationship between residential proximity to extremely low frequency electromagnetic fields from power grids and risk of birth defects. We analyzed a population-based sample of 2,164,246 infants born in Quebec, Canada between 1989 and 2016. We geocoded the maternal residential postal code at delivery and computed the distance to the nearest high voltage electrical transmission line or transformer station. We used log-binomial regression to estimate risk ratios (RR) and 95% confidence intervals (CI) for the association of residential proximity to transmission lines and transformer stations with birth defects, adjusting for maternal and infant characteristics. The prevalence of birth defects within 200 m of a transmission line (579.4 per 10,000 per live births) was only slightly higher compared with distances further away (568.7 per 10,000). A similar trend was seen for transformer stations. Compared with 200 m, a distance of 50 m was not associated with the risk of birth defects for transmission lines (RR 1.00, 95% CI 1.00-1.01) and transformer stations (RR 1.01, 95% CI 1.00-1.03). There was no consistent association when we examined birth defects in different organ systems. We found no compelling evidence that residential proximity to extremely low frequency electromagnetic fields from electrical power grids increases the risk of birth defects. Women residing near electrical grids can be reassured that an effect on the risk of birth defects is unlikely.

The clinical significance of Xp22.31 microduplication is controversial as it is reported in subjects with developmental delay (DD), their unaffected relatives and unrelated controls. We performed multifaceted studies in a family of a boy with hypotonia, dysmorphic features and DD who carried a 600 Kb Xp22.31 microduplication (7515787-8123310bp, hg19) containing two genes, VCX and PNPLA4. The duplication was transmitted from his cognitively normal maternal grandfather. We found no evidence of the duplication causing the proband's DD and congenital anomalies based on unaltered expression of PNPLA4 in the proband and his mother in comparison to controls and preferential activation of the paternal chromosome X with Xp22.31 duplication in proband's mother. However, a de novo, previously reported deleterious, missense mutation in Pur-alpha gene (PURA) (5q31.2), with a role in neuronal differentiation was detected in the proband by exome sequencing. We propose that the variability in the phenotype in carriers of Xp22.31 microduplication can be due to a second and more deleterious genetic mutation in more severely affected carriers. Widespread use of whole genome next generation sequencing in families with Xp22.31 CNV could help identify such cases.

Background: Following an unexplained cardiac arrest, clinical genetic testing is increasingly becoming standard of care. Periodic review of variant classification is required, as reinterpretation can change the diagnosis, prognosis, and management of patients and their relatives. Methods: This study aimed to develop and validate a standardized algorithm to facilitate clinical application of the 2015 American College of Medical Genetics and Association for Molecular Pathology guidelines for the interpretation of genetic variants. The algorithm was applied to genetic results in the Cardiac Arrest Survivors With Preserved Ejection Fraction Registry, to assess the rate of variant reclassification over time. Variant classifications were then compared with the classifications of 2 commercial laboratories to determine the rate and identify sources of variant interpretation discordance. Results: Thirty-one percent of participants (40 of 131) had at least 1 genetic variant with a clinically significant reclassification over time. Variants of uncertain significance were more likely to be downgraded (73%) to benign than upgraded to pathogenic (27%; P =0.03). For the second part of the study, 50% (70 of 139) of variants had discrepant interpretations (excluding benign variants), provided by at least 1 team. Conclusions: Periodic review of genetic variant classification is a key component of follow-up care given rapidly changing information in the field. There is potential for clinical care gaps with discrepant variant interpretations, based on the interpretation and application of current guidelines. The development of gene- and disease-specific guidelines and algorithms may provide an opportunity to further standardize variant interpretation reporting in the future. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00292032.

Background Assessing the issues surrounding predictive genetic testing for children at risk of an inherited arrhythmia or cardiomyopathy is complex. The objective of this study was to design and evaluate 4 cardiac decision aids. The decision aids were developed to assist families with a genetic diagnosis of long QT syndrome, hypertrophic cardiomyopathy, dilated cardiomyopathy, or arrhythmogenic right ventricular cardiomyopathy in deciding between predictive genetic testing and cardiac screening for their children. Methods The decision aids were developed with the use of the International Patient Decision Aid Standards framework and revised based on feedback from individuals with lived experience, genetic counsellors, and other health professionals. Results Response to the decision aids was positive, and acceptability and understandability scores were high. Conclusions The decision aids can be used before, during or after a genetic counselling appointment as a resource or to guide discussion. These tools permit a balanced and consistent approach to the decision-making process, with a focus on the importance families place on the advantages and disadvantages of each option.

Objective: Infectious illness, including lower respiratory tract infection (LRTI), is a leading cause of childhood morbidity and infant mortality in Inuit children in Nunavut Canada. The carnitine palmitoyltransferase 1A (CPT1A) p.P479L variant is common in arctic Indigenous populations of Alaska, Canada, and Greenland. CPT1A is a fatty acid oxidation enzyme expressed in the liver, immunocytes and other tissues, and is needed to use fats for energy during fasting. Previous association of the variant with early childhood infectious illness and infant death has been challenged because of sample size and limited adjustment for confounders. We evaluated whether the p.P479L variant is associated with infectious illness in Inuit children of Nunavut, Canada. Methods: We conducted a retrospective clinical chart review of 2,225 Inuit children (0–5 years) for infectious illness (including otitis media, gastroenteritis, and hospital admission for LRTI), prenatal, perinatal, and socioeconomic indicators, subsequently linking to CPT1A genotype. Multivariable logistic regression adjusted for birth characteristics, breastfeeding, maternal smoking, food insecurity, and socioeconomic indicators. Results: Overall, 27% of children were hospitalized for LRTI, 86% had otitis media and 50% had gastroenteritis. The p.P479L allele frequency was 0.82. In multivariable analysis, p.P479L homozygosity was associated with LRTI admission (aOR:2.88 95%CI:1.46–5.64), otitis media (aOR:1.83, 95%CI:1.05–3.21), and gastroenteritis (aOR:1.74, 95%CI:1.09–2.77), compared to non-carriers. Conclusion: Children homozygous for the p.P479L variant were more likely to experience infectious illness than non-carriers, including hospitalization for respiratory tract infections. Given the role of CPT1A in immunocytes, our findings indicate that more study is needed to determine if there is a role of the variant in immune response. Continued Inuit involvement is essential when considering next steps.

BACKGROUND Following an unexplained cardiac arrest, patients and family members typically undergo a comprehensive series of investigations to identify the underlying cause of arrest, with a diagnosis identified in more than half of cardiac arrest survivors. However, the long-term arrhythmic outcomes among cardiac arrest survivors remains unclear. METHODS AND RESULTS The Cardiac Arrest Survivors with Preserved Ejection Fraction Registry (CASPER) prospectively enrolls cardiac arrest survivors and their first-degree relatives (FDR) across 16 Canadian centers. Patient demographics, cardiac investigations, working diagnoses, and follow-up events are recorded. Those with a history of significant coronary artery disease or manifest cause of cardiac arrest are excluded. Arrhythmic events, including implantable cardioverter-defibrillator (ICD) shock or anti-tachycardia pacing (ATP) are recorded. Patients with at least one follow-up visit were included. Hazard ratios for arrhythmic events were calculated using Cox proportional hazards models. 741 patients were enrolled, with a median age of 42 years (interquartile range [IQR] 29-53), 56% being male, and mostly Caucasian (82%). Patients included cardiac arrest suvivors/probands (n=480, 66%) and first-degree relatives (n=243, 34%). In addition to baseline investigations, patients undertook signal-averaged ECG (56%), exercise testing (70%), extended monitoring (50%), cardiac MRI (62%), and provocative testing with procainamide (39%), adrenaline (31%) or an electrophysiologic study (14%). After excluding 18 patients with ongoing diagnosis adjudication, the working diagnoses of probands and FDRs are reported in the Table. Working diagnoses among probands were divided into three categories, including unexplained/idiopathic (after comprehensive investigations, n=351), structural/cardiomyopathy (including arrhythmogenic right ventricular cardiomyopathy and others, n=64), and electrical/channelopathy (including Long QT Syndrome, Brugada Syndrome, and others, n=65). During a median follow-up of 3.3 years (IQR 1.7-5.9), 69 patients (9%) suffered an ICD shock or ATP with a median time-to-event of 1.0 years (IQR 0.5-2.8). Probands had a significantly higher rate of events (hazard ratio [HR] 16.9, 95% confidence interval [CI] 4.1-69.0, p CONCLUSION In a cohort of unexplained cardiac arrest survivors and first-degree relatives, probands had a significant rate of recurrent events. Probands with structural/cardiomyopathy diagnoses had twice the risk of arrhythmia recurrence. Patients with structural diagnoses may be more likely to have arrhythmic events in follow-up, potentially due to a progressive disease process compared to other diagnoses.

Causes of death in children with birth defects are poorly understood.To determine mortality rates by cause of death in children with and without birth defects.This longitudinal cohort study included a population-based sample of 1 037 688 children and was conducted in all hospitals in Quebec, Canada, with 7 700 596 person-years of follow-up between birth and age 14 years (April 1, 2006, to March 31, 2020).Presence or absence of a birth defect.Outcomes were all-cause and cause-specific mortality. Hazard ratios (HRs) and 95% CIs were computed for the association between birth defects and mortality with Cox proportional hazards models adjusted for patient characteristics.Among the 1 037 688 children in the cohort, 95 566 had birth defects (56.5% boys). There were 532 542 boys in the cohort (51.3%), and mean (SD) age at the end of follow-up was 7.42 (3.72) years. There were 918 deaths among children with defects, and the mean (SD) age was 0.93 (2.07) years at death; there were 1082 deaths among the 942 122 children without defects, and the mean (SD) age at death was 0.50 (1.51) years. Mortality rates were higher for children with birth defects compared with no defect (1.3 vs 0.2 deaths per 1000 person-years, respectively). Girls (HR, 5.66; 95% CI, 4.96-6.47) and boys (HR, 4.69; 95% CI, 4.15-5.29) with birth defects had an elevated risk of death before 14 years compared with unaffected children. Birth defects were associated with mortality from circulatory (HR, 26.59; 95% CI, 17.73-39.87), respiratory (HR, 23.03; 95% CI, 15.09-35.14), and digestive causes (HR, 31.77; 95% CI, 11.87-85.04), but anomalies were rarely listed as the cause of death. Compared with children with no defect, those with birth defects were at greatest risk of death between 28 and 364 days of life.This cohort study of 1 037 688 children suggests that birth defects were strongly associated with mortality owing to circulatory, respiratory, and digestive causes. This finding suggests that the contribution of birth defects may be underestimated in mortality statistics.

The archaic definition and registration processes for stillbirth currently prevalent in Canada impede both clinical care and public health. The situation is fraught because of definitional problems related to the inclusion of induced abortions at ≥20 weeks' gestation as stillbirths: widespread uptake of prenatal diagnosis and induced abortion for serious congenital anomalies has resulted in an artefactual temporal increase in stillbirth rates in Canada and placed the country in an unfavourable position in international (stillbirth) rankings. Other problems with the Canadian stillbirth definition and registration processes extend to the inclusion of fetal reductions (for multi-fetal pregnancy) as stillbirths, and the use of inconsistent viability criteria for reporting stillbirth. This paper reviews the history of stillbirth registration in Canada, provides a rationale for updating the definition of fetal death and recommends a new definition and improved processes for fetal death registration. The recommendations proposed are intended to serve as a starting point for reformulating issues related to stillbirth, with the hope that building a consensus regarding a definition and registration procedures will facilitate clinical care and public health.RéSUMé: La définition et les méthodes d’enregistrement archaïques des mortinaissances qui prévalent actuellement au Canada entravent à la fois les soins cliniques et la santé publique. La situation est délicate à cause des problèmes de définition que pose l’inclusion des avortements provoqués à ≥ 20 semaines de gestation parmi les mortinaissances : le recours généralisé au diagnostic prénatal et les avortements provoqués en cas d’anomalies congénitales graves ont entraîné une augmentation temporelle artéfactuelle des taux de mortinatalité au Canada et placé le pays dans une position défavorable dans les classements internationaux (de la mortinatalité). Les autres problèmes dans la définition et les méthodes d’enregistrement canadiennes des mortinaissances sont l’inclusion de la réduction fœtale (pour les grossesses multifœtales) parmi les mortinaissances et l’emploi de critères de viabilité inconsistants pour déclarer les mortinaissances. Nous examinons ici l’histoire de l’enregistrement des mortinaissances au Canada, nous justifions une révision possible de la définition de la mort fœtale et nous recommandons une nouvelle définition et des méthodes d’enregistrement améliorées des morts fœtales. Les recommandations proposées se veulent un point de départ à une reformulation des questions liées à la mortinatalité, dans l’espoir que l’établissement d’un consensus sur une définition et sur les méthodes d’enregistrement facilitera les soins cliniques et la santé publique.

Coeliac disease (CD) is prevalent in patients of reproductive age, but the impact on pregnancy and fetal development is unclear. The British Society of Gastroenterology recommends serological testing for CD in patients with chronic diarrhoea,1 but CD may be under-recognised in women without the classic symptoms.2 We studied the association between CD and the risk of birth defects in pregnant women. We analysed a cohort of live births between 1989 and 2016 in Quebec, Canada using discharge summaries from the Maintenance and Use of Data for the Study of Hospital Clientele database. We used diagnostic codes to identify women with CD and infants with different types of birth defects. We determined whether CD was present during prenatal follow-up, or if women required hospitalisation for CD before or after pregnancy. We used log-binomial regression models with robust SE to estimate associations between CD and birth defects adjusted for maternal characteristics. This study comprised 2 184 888 infants, including 125 081 …

Addressing Indigenous rights and interests in genetic resources has become increasingly challenging in an open science environment that promotes unrestricted access to genomic data. Although Indigenous experiences with genetic research have been shaped by a series of negative interactions, there is increasing recognition that equitable benefits can only be realized through greater participation of Indigenous communities. Issues of trust, accountability and equity underpin Indigenous critiques of genetic research and the sharing of genomic data. This Perspectives article highlights identified issues for Indigenous communities around the sharing of genomic data and suggests principles and actions that genomic researchers can adopt to recognize community rights and interests in data.

Background and AimsThe relationship between inflammatory bowel disease in pregnancy and birth defects is not understood. We evaluated whether Crohn’s disease and ulcerative colitis in pregnant women were associated with the risk of birth defects in the offspring.MethodsWe undertook a retrospective cohort study of 2 184 888 pregnancies in Quebec, Canada, between 1989 and 2016. We calculated risk ratios [RR] and 95% confidence intervals [CI] for the association between inflammatory bowel disease and the risk of birth defects, using generalised estimating equations adjusted for maternal characteristics. We assessed associations in the period before 2000, when immunosuppressive biologic therapy and folic acid food fortification were not yet available, compared with the period after 2000 when these interventions were more widespread.ResultsThis study included 13 099 women with Crohn’s disease and 7798 with ulcerative colitis. Crohn’s disease was associated with 1.90 times [95% CI 1.10–3.28] the risk of abdominal wall defects [gastroschisis, omphalocoele, and diaphragmatic hernia] and ulcerative colitis was associated with 1.53 times [95% CI 1.02–2.30] the risk of central nervous system defects. The association of Crohn’s disease with abdominal wall defects was stronger before 2000 [RR 3.62, 95% CI 1.71–7.67] than after 2000 [RR 1.23, 95% CI 0.55–2.75]. Ulcerative colitis was associated with central nervous system defects regardless of time period.ConclusionsThese findings suggest that inflammatory bowel disease is associated with the risk of abdominal wall and central nervous system defects, and that introduction of immunobiologic medications is unlikely to be associated with added risk.PodcastThis article has an associated podcast which can be accessed at https://academic.oup.com/ecco-jcc/pages/podcast

BACKGROUND: The hepatic carnitine palmitoyltransferase I (CPT1A) p.P479L variant is common in Aboriginal populations across coastal British Columbia, Alaska, the Canadian North, and Greenland. While the high frequency of this variant suggests positive selection, other studies have shown an association with sudden unexpected death in infancy and infection. We utilized administrative health data to evaluate hospitalizations for a single year cohort of children of First Nations descent genotyped for the variant and, matched for location of birth. Seven years of data were reviewed for 150 children split evenly between CPT1A genotypes (homozyous, heterozygous, and noncarrier of the p.P479L variant). RESULTS: Children homozygous for the p.P479L allele had a higher rate of hospital admissions at 2.6 per individual as compared to noncarriers at 0.86. Heterozygous children also showed a significant increase at 1.9 per person. Length of stay per admission was increased for both p.P479L homozygotes and heterozygotes. The odds ratio (OR) for at least one hospitalization for any reason was increased for p.P479L homozygotes relative to noncarriers (OR=10.2, confidence interval [CI] 3.5 to 30.0) as were admissions for dental caries (OR=3.4, CI 1.5 to 7.8), acute lower respiratory tract infections (OR=6.0, CI 1.6 to 22.4), and otitis media (OR=13.5, CI 1.7 to 109.4). CONCLUSIONS: The CPT1A p.P479L variant is associated with an increased rate of hospitalization for those homozygous, primarily for infectious disease causes. Heterozygotes also showed a small but significant increase in hospitalization rates suggesting some dosage effect. Functional studies will be required to identify the underlying pathological mechanism.

Background: The benefits of folic acid for prevention of congenital anomalies are well known. For the Inuit of Canada, where vitamin use is low and access to folate-rich foods limited, fortification is likely a major source of intake. We sought to determine whether red blood cell folate (RBCF) levels of Inuit women reached accepted target levels. Methods: The Inuit Health Survey, 2007–2008, included evaluation of RBCF levels among 249 randomly selected non-pregnant women of reproductive age. Using descriptive statistics and linear regression analyses, RBCF levels were assessed and compared across several socio-demographic variables to evaluate the characteristics associated with RBCF status. Results: Mean (SD) RBCF levels of 935.5 nmol/L (± 192) reached proposed target levels (> 906 nmol/L); however, 47% of women had lower than target levels. In bivariate analysis, non-smoking, higher education, higher income, food security, increased body mass index, and vitamin use were each significantly associated with higher RBCF. Increased levels of smoking had a negative association with RBCF levels (− 5.8 nmol/L per cigarette smoked per day (p = 0.001)). A total of 6.8% of women reported taking vitamin supplements, resulting in a 226 nmol/L higher RBCF level on average compared to non-users (p