Exome sequencing identifies rare variants in multiple genes in atrioventricular septal defect.

PURPOSE: The genetic etiology of atrioventricular septal defect (AVSD) is unknown in 40% cases. Conventional sequencing and arrays have identified the etiology in only a minority of nonsyndromic individuals with AVSD. METHODS: Whole-exome sequencing was performed in 81 unrelated probands with AVSD to identify potentially causal variants in a comprehensive set of 112 genes with strong biological relevance to AVSD. RESULTS: A significant enrichment of rare and rare damaging variants was identified in the gene set, compared with controls (odds ratio (OR): 1.52; 95% confidence interval (CI): 1.35-1.71; P = 4.8 × 10(-11)). The enrichment was specific to AVSD probands, compared with a cohort without AVSD with tetralogy of Fallot (OR: 2.25; 95% CI: 1.84-2.76; P = 2.2 × 10(-16)). Six genes (NIPBL, CHD7, CEP152, BMPR1a, ZFPM2, and MDM4) were enriched for rare variants in AVSD compared with controls, including three syndrome-associated genes (NIPBL, CHD7, and CEP152). The findings were confirmed in a replication cohort of 81 AVSD probands. CONCLUSION: Mutations in genes with strong biological relevance to AVSD, including syndrome-associated genes, can contribute to AVSD, even in those with isolated heart disease. The identification of a gene set associated with AVSD will facilitate targeted genetic screening in this cohort.

User-Centered Design and Usability of Voxe as a Pediatric Electronic Patient-Reported Outcome Measure Platform: Mixed Methods Evaluation Study.

BACKGROUND: Electronic patient-reported outcome measures (ePROMs) are standardized digital instruments integrated into clinical care to collect subjective data regarding patients' health-related quality of life, functional status, and symptoms. In documenting patient-reported progress, ePROMs can guide treatment decisions and encourage measurement-based care practices. Voxe is a pediatric and user-centered ePROM platform for patients with chronic health conditions. OBJECTIVE: We aimed to describe the user-centered design approach involving feedback from end users and usability testing of Voxe's platform features to support implementation in a pediatric health care setting. METHODS: Purposive sampling was used to recruit patients aged 8-17 years from 2 chronic illness populations in 2 pediatric hospitals in Canada. Patients' health care team members were also purposively recruited. One-on-one iterative testing sessions were conducted digitally by research team members with participants to obtain feedback on the appearance and functionalities of the Voxe platform prototype. Patients and health care providers (HCPs) completed Voxe-related task-based activities. International Organization for Standardization key performance indicators were tracked during HCP task-based activities. HCPs also completed the System Usability Scale. To test platform usability, the think-aloud technique was used by participants during the completion of structured tasks. After completing all task-based activities, patient participants selected 5 words from the Microsoft Desirability Toolkit to describe their overall impression and experience with the Voxe platform. Qualitative data about likes, dislikes, and ease of use were collected through semistructured interviews. Feedback testing sessions were conducted with patients and HCPs until Voxe was acceptable to participating end users, with no further refinements identified. Quantitative and qualitative data analysis were completed using descriptive statistics and content analysis. RESULTS: A total of 49 patients and 38 HCPs were recruited. Patients were positive about Voxe's child-centered design characteristics and notification settings. HCPs rated Voxe as user-friendly and efficient, with the time to complete tasks decreasing over time. HCPs were satisfied with the Voxe platform functionalities and identified the value of Voxe's system notifications, summarized display of ePROM results, and its capacity to integrate with electronic medical records. Patients' and HCPs' high satisfaction rates with the Voxe prototype highlight the importance of being responsive to user suggestions from the inception of eHealth platform developments to ensure their efficient and effective design. CONCLUSIONS: This paper describes the user-centered creation and usability testing of Voxe as an ePROM platform for implementation into clinical care for pediatric patients with chronic health conditions. As a patient-facing platform that can be integrated into electronic medical records, Voxe aligns with measurement-based care practices to foster quality patient-centered approaches to care. End users' positive feedback and evaluation of the platform's user-friendliness and efficiency suggest that Voxe represents a valuable and promising solution to systematically integrate patient-related outcome (PRO) data into complex and dynamic clinical health care settings. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1136/bmjopen-2021-053119.

Decentralized study of COVID Vaccine Antibody Response (STOPCoV): Results of a participant satisfaction survey.

The Covid-19 pandemic required many clinical trials to adopt a decentralized framework to continue research activities during lock down restrictions. The STOPCoV study was designed to assess the safety and efficacy of Covid-19 vaccines in those aged 70 and above compared to those aged 30-50 years of age. In this sub-study we aimed to determine participant satisfaction for the decentralized processes, accessing the study website and collecting and submitting study specimens. The satisfaction survey was based on a Likert scale developed by a team of three investigators. Overall, there were 42 questions for respondents to answer. The invitation to participate with a link to the survey was emailed to 1253 active participants near the mid-way point of the main STOPCoV trial (April 2022). The results were collated and answers were compared between the two age cohorts. Overall, 70% (83% older, 54% younger cohort, no difference by sex) responded to the survey. The overall feedback was positive with over 90% of respondents answering that the website was easy to use. Despite the age gap, both the older cohort and younger cohort reported ease of performing study activities through a personal electronic device. Only 30% of the participants had previously participated in a clinical trial, however over 90% agreed that they would be willing to participate in future clinical research. Some difficulties were noted in refreshing the browser whenever updates to the website were made. The feedback attained will be used to improve current processes and procedures of the STOPCoV trial as well as share learning experiences to inform future fully decentralized research studies.

Predictors of Breakthrough SARS-CoV-2 Infection after Vaccination.

The initial two-dose vaccine series and subsequent booster vaccine doses have been effective in modulating SARS-CoV-2 disease severity and death but do not completely prevent infection. The correlates of infection despite vaccination continue to be under investigation. In this prospective decentralized study (n = 1286) comparing antibody responses in an older- (≥70 years) to a younger-aged cohort (aged 30-50 years), we explored the correlates of breakthrough infection in 983 eligible subjects. Participants self-reported data on initial vaccine series, subsequent booster doses and COVID-19 infections in an online portal and provided self-collected dried blood spots for antibody testing by ELISA. Multivariable survival analysis explored the correlates of breakthrough infection. An association between higher antibody levels and protection from breakthrough infection observed during the Delta and Omicron BA.1/2 waves of infection no longer existed during the Omicron BA.4/5 wave. The older-aged cohort was less likely to have a breakthrough infection at all time-points. Receipt of an original/Omicron vaccine and the presence of hybrid immunity were associated with protection of infection during the later Omicron BA.4/5 and XBB waves. We were unable to determine a threshold antibody to define protection from infection or to guide vaccine booster schedules.

COVID-19 vaccine antibody responses in community-dwelling adults to 48 weeks post primary vaccine series.

We report a decentralized prospective cohort study of self-reported adverse events and antibody responses to COVID vaccines derived from dried blood spots. Data are presented for 911 older (aged >70 years) and 375 younger (30-50 years) recruits to 48 weeks after the primary vaccine series. After a single vaccine, 83% younger and 45% older participants had overall seropositivity (p < 0.0001) increasing to 100/98% with the second dose, respectively (p = 0.084). A cancer diagnosis (p = 0.009), no mRNA-1273 vaccine doses (p <0 .0001), and older age (p <0 .0001) predicted lower responses. Antibody levels declined in both cohorts at 12 and 24 weeks increasing with booster doses. At 48 weeks, for participants with 3 vaccine doses, the median antibody levels were higher in the older cohort (p = 0.04) with any dose of mRNA-1273 (p <0 .0001) and with COVID infection (p <0 .001). The vaccines were well tolerated. Breakthrough COVID infections were uncommon (16% older cohort, 29% younger cohort; p < 0.0001) and mild.

Creation of an electronic patient-reported outcome measure platform Voxe: a mixed methods study protocol in paediatric solid organ transplantation.

INTRODUCTION: Patient-reported outcome measures (PROMs) provide an opportunity for meaningful patient engagement and shared decision-making. The objective of this research programme is to improve health outcomes for paediatric solid organ transplant patients by implementing PROMs into clinical care. The current study aims to create Voxe, a paediatric user-centred electronic PROM platform, by engaging patients and healthcare providers throughout the design and development process. METHODS AND ANALYSIS: The creation of Voxe will occur over two phases that build on previous research. The user interface design phase employs a 'user-centric' approach to identify end-users' needs and iteratively refine the look and layout of Voxe to meet these needs. Transplant recipients, aged 10-17, and healthcare providers will participate in three rounds of testing (24 participants total). Participants will: (1) complete task-based activities (outcomes-effectiveness and efficiency), (2) complete questionnaires (outcome-satisfaction) and (3) participate in a semi-structured interview. The following phase involves software development and Voxe usability testing. Transplant recipients, aged 8-17, and healthcare providers will participate in four rounds of iterative testing (24-40 participants total). The think-aloud technique will be employed, and participants will describe their thoughts and feelings while interacting with a Voxe prototype. Participants will: (1) log into Voxe and complete tasks (outcomes-time on task, successful task completion, frequency of critical and non-critical errors and error-free rate), (2) complete questionnaires (outcome-satisfaction) and (3) participate in a semi-structured interview. Findings will result in the creation and launch of a user-centred electronic PROM platform. ETHICS AND DISSEMINATION: Research ethics board approval has been provided by The Hospital for Sick Children. This research is critical to answering methodological and operational questions to inform Voxe implementation in paediatric clinical settings and facilitate PROM data collection. Future investigations will include an implementation-effectiveness evaluation.

Prospective observational study and serosurvey of SARS-CoV-2 infection in asymptomatic healthcare workers at a Canadian tertiary care center.

Health care workers (HCWs) are at higher risk for SARS-CoV-2 infection and may play a role in transmitting the infection to vulnerable patients and members of the community. This is particularly worrisome in the context of asymptomatic infection. We performed a cross-sectional study looking at asymptomatic SARS-CoV-2 infection in HCWs. We screened asymptomatic HCWs for SARS-CoV-2 via PCR. Complementary viral genome sequencing was performed on positive swab specimens. A seroprevalence analysis was also performed using multiple assays. Asymptomatic health care worker cohorts had a combined swab positivity rate of 29/5776 (0.50%, 95%CI 0.32-0.75) relative to a comparative cohort of symptomatic HCWs, where 54/1597 (3.4%) tested positive for SARS-CoV-2 (ratio of symptomatic to asymptomatic 6.8:1). SARS-CoV-2 seroprevalence among 996 asymptomatic HCWs with no prior known exposure to SARS-CoV-2 was 1.4-3.4%, depending on assay. A novel in-house Coronavirus protein microarray showed differing SARS-CoV-2 protein reactivities and helped define likely true positives vs. suspected false positives. Our study demonstrates the utility of routine screening of asymptomatic HCWs, which may help to identify a significant proportion of infections.

Adrenergic receptor genotypes influence postoperative outcomes in infants in the Single-Ventricle Reconstruction Trial.

OBJECTIVES: Adrenergic receptor (ADR) genotypes have been associated with adverse outcomes in heart failure. Our objective was to evaluate the association of ADR genotypes with post-Norwood outcomes in infants with hypoplastic left heart syndrome (HLHS). METHODS: Infants with HLHS participating in the Pediatric Heart Network Single-Ventricle Reconstruction Trial underwent genotyping for 4 single-nucleotide polymorphisms in 3 ADR genes: ADRB1_231A/G, ADRB1_1165G/C, ADRB2_5318C/G, and ADRA2A_2790C/T. The association of genotype with freedom from serious adverse events (SAEs) (death, transplant, extracorporeal membrane oxygenation, cardiopulmonary resuscitation, acute shunt failure, unplanned reoperations, or necrotizing enterocolitis) during 14 months' follow-up was assessed with Cox regression and the association with post-Norwood complications was assessed with Poisson regression. Models were adjusted for clinical and surgical factors. RESULTS: The study included 351 eligible patients (62% male; 83% white). The mean age at Norwood procedure was 5.6 ± 3.6 days. A total of 152 patients had SAEs during 14-month follow-up including 84 deaths and 10 transplants. ADRA2A_2790CC genotype had lower SAE-free survival compared with CT/TT genotypes during follow-up (Log rank test, P = .02), and this association was independent of clinical and surgical risk factors (adjusted Cox regression, hazard ratio 1.54 [95% confidence interval 1.04, 2.30] P = .033). Post-Norwood complication rate did not differ by genotype. CONCLUSIONS: Infants with HLHS harboring ADR genotypes that are associated with greater catecholamine release or sensitivity had lower event-free survival after staged palliation. Excess catecholamine activation may adversely affect cardiovascular adaptation after the Norwood procedure. Future studies should explore whether targeting adrenergic activation in those harboring risk genotypes can improve outcomes. (ClinicalTrials.gov number NCT00115934).

Distinct genetic architectures for syndromic and nonsyndromic congenital heart defects identified by exome sequencing.

Congenital heart defects (CHDs) have a neonatal incidence of 0.8-1% (refs. 1,2). Despite abundant examples of monogenic CHD in humans and mice, CHD has a low absolute sibling recurrence risk (∼2.7%), suggesting a considerable role for de novo mutations (DNMs) and/or incomplete penetrance. De novo protein-truncating variants (PTVs) have been shown to be enriched among the 10% of 'syndromic' patients with extra-cardiac manifestations. We exome sequenced 1,891 probands, including both syndromic CHD (S-CHD, n = 610) and nonsyndromic CHD (NS-CHD, n = 1,281). In S-CHD, we confirmed a significant enrichment of de novo PTVs but not inherited PTVs in known CHD-associated genes, consistent with recent findings. Conversely, in NS-CHD we observed significant enrichment of PTVs inherited from unaffected parents in CHD-associated genes. We identified three genome-wide significant S-CHD disorders caused by DNMs in CHD4, CDK13 and PRKD1. Our study finds evidence for distinct genetic architectures underlying the low sibling recurrence risk in S-CHD and NS-CHD.

High throughput exome coverage of clinically relevant cardiac genes.

BACKGROUND: Given the growing use of whole-exome sequencing (WES) for clinical diagnostics of complex human disorders, we evaluated coverage of clinically relevant cardiac genes on WES and factors influencing uniformity and depth of coverage of exonic regions. METHODS: Two hundred and thirteen human DNA samples were exome sequenced via Illumina HiSeq using different versions of the Agilent SureSelect capture kit. 50 cardiac genes were further analyzed including 31 genes from the American College of Medical Genetics (ACMG) list for reporting of incidental findings and 19 genes associated with congenital heart disease for which clinical testing is available. Gene coordinates were obtained from two databases, CCDS and Known Gene and compared. Read depth for each region was extracted from the exomes and used to assess capture variability between kits for individual genes, and for overall coverage. GC content, gene size, and inter-sample variability were also tested as potential contributors to variability in gene coverage. RESULTS: All versions of capture kits (designed based on Consensus coding sequence) included only 55% of known genomic regions for the cardiac genes. Although newer versions of each Agilent kit showed improvement in capture of CCDS regions to 99%, only 64% of Known Gene regions were captured even with newer capture kits. There was considerable variability in coverage of the cardiac genes. 10 of the 50 genes including 6 on the ACMG list had less than the optimal coverage of 30X. Within each gene, only 32 of the 50 genes had the majority of their bases covered at an interquartile range ≥30X. Heterogeneity in gene coverage was modestly associated with gene size and significantly associated with GC content. CONCLUSIONS: Despite improvement in overall coverage across the exome with newer capture kit versions and higher sequencing depths, only 50% of known genomic regions of clinical cardiac genes are targeted and individual gene coverage is non-uniform. This may contribute to a bias with greater attribution of disease causation to mutations in well-represented and well-covered genes. Improvements in WES technology are needed before widespread clinical application.

Personalized medicine in the care of the child with congenital heart disease: discovery to application.

On October 27-28, 2012, the SickKids Labatt Family Heart Centre and the Heart Centre Biobank Registry hosted the second international GenomeHeart symposium in Toronto, Ontario. The symposium featured experts in cardiology, developmental biology, pharmacology, genomics, bioinformatics, stem cell biology, biobanking, and ethics. The theme of this year's symposium was the application of emerging technologies in genomics, proteomics, transcriptomics, and bioinformatics to diagnostics and therapeutics of the child with heart disease. Social, ethical, and economic issues were also discussed in the context of clinical translation. We highlight some of the themes that emerged from this exciting 2-day event.