Robust evidence is required to support decision-making about incorporating genomics into healthcare; patient perspectives are crucial. Prior studies centre on people giving research consent for testing, yet significant differences between research and clinical cohorts are well established. We investigated 1690 patients offered genomic testing during clinical care by a range of medical specialists, for rare diseases and cancer. Ninety per cent (1515) accepted testing. Of 74 decliners providing their reasons, 20 gave genomic-specific concerns. Impact and experiences of care were captured using surveys after consent (S1:RR 73%) and return of results (S2:RR 53%). We actively included those often missing from research, e.g. 8% of S2 respondents accepted telephone assistance - typically with interpreters - to complete surveys. Those who spoke English as an additional language were less likely to have received enough information at pre-test counselling (88% v 96%) and less likely to correctly answer questions about potential genomic test results. After receiving results, 10% (52/534) of respondents had moderate-high decision regret; predictors included English as an additional language and not receiving enough information at consent. Value from testing was quantified and compared: those with informative results valued their medical and personal utility; those with uninformative results derived social utility. Perceived personal control increased post-result for those with diagnostic results and decreased for those with uninformative results. Our results expand the evidence base available for genomic health technology assessment. On balance, genomic test results provide more value than harm, but equity issues need to be addressed to ensure all patients can benefit.

ABSTRACT Despite recent advances in next-generation sequencing, genetic diagnostic rates for dilated cardiomyopathy (DCM) remain low. Among paediatric DCM, causes are often heritable, with a greater frequency of de novo , recessive and syndromic causes of disease. Novel diagnostic methods are therefore required to solve monogenic cases. To assess the value of proteomics as a diagnostic tool for paediatric DCM, we obtained left ventricle myocardial samples from paediatric patients undergoing heart transplantation at the Royal Children’s Hospital, Melbourne. We performed genome sequencing and proteomics and leveraged this multi-omics dataset to uncover the molecular cause of disease in a gene elusive proband. The proband carried a heterozygous JPH2 frameshift variant identified on clinical exome sequencing. However, proteomic analysis showed a pronounced downregulation of JPH2, suggestive of biallelic loss-of-function. Closer inspection of the genomic data revealed a large inversion (∼8.34 Mb) with a breakpoint falling within intron 5 of JPH2 that displaces the 3′UTR from the coding transcript. The two variants were confirmed to be in trans using long read DNA sequencing, consistent with a diagnosis of JPH2 autosomal recessive DCM. Finally, we applied RNA sequencing with total RNA library preparation to show that transcripts containing a 3′UTR were reduced to ∼10% relative to controls. As a proof-of-principle, we present the first reported use of proteomics from explanted cardiac tissue to provide a genetic diagnosis. Our methodology has broad relevance to patients with genetically unsolved Mendelian diseases, who might undergo organ transplantation as part of clinical management.

Background: Variants in JPH2 -encoded junctophilin 2 have been associated with a range of cardiac diseases, including hypertrophic cardiomyopathy, dilated cardiomyopathy, arrhythmias, and sudden cardiac death. Despite these associations, due to its rarity, there is limited understanding of the penetrance and clinical spectrum of disease. Defining the clinical impact of JPH2 variants is essential for enhancing risk assessment, early diagnosis, and guiding clinical management in this rare disease. Objective: To determine the penetrance and cardiac phenotypic spectrum associated with JPH2 -mediated disease. Methods: An international, multi-center registry of JPH2 variant-positive individuals was developed from participating clinical sites and the literature. Inclusion criteria were 1) a diagnostic JPH2 variant by ACMG criteria (likely pathogenic/pathogenic LP/P) or a variant of uncertain significance (VUS) in JPH2 , and 2) at least 1 cardiac evaluation. Exclusion criteria were 1) variant rated likely benign/benign (LB/B) by ACMG and/or 2) presence of a compound rare/diagnostic variant in a known cardiomyopathy-associated gene. Heart failure was defined as LVEF ≤ 40, a clinical diagnosis of heart failure, or a heart transplant. Results: Fifty-nine cases were identified for this cohort, making it the largest cohort of JPH2 -positive cases to date. Of the cohort, 61% were male, 27% were female, and 12% had unknown gender. Among the variants identified, 88% were monoallelic, 10% were biallelic, and 2% had unknown zygosity. Of the monoallelic variants, 6% were loss-of-function (LOF) variants and 94% were missense variants. Within the cohort, 33% of participants with biallelic variants developed HF compared to 12% of those with monoallelic missense variants. Overall, 15% of the participants developed heart failure. Based on ACMG classification, 67% of individuals who developed heart failure had LP/P variants, while 33% had a VUS. In terms of broader cardiac manifestations, participants in this cohort, 76% developed cardiomyopathy, 58% developed arrhythmias, 3% had congenital heart disease, 3% had other types of cardiovascular disease, and 12% had no cardiac manifestations. Conclusions: JPH2 variants appear to have high penetrance, likely driven by variant type, and primarily manifest as cardiomyopathy and arrhythmias.

Inherited cardiac conditions (ICCs), like inherited cardiomyopathies (ICMs) and long QT syndrome (LQTS), are serious genetic conditions that carry a risk of sudden death. Predictive genetic testing (PT) is routinely available, however, the impact of this testing during the adolescent period is understudied. To understand the lived experience of young people who have undergone PT for ICCs, semi-structured, in-depth interviews were conducted with young people who underwent PT for an ICC between the ages of 10–17 years between January 2009 and July 2020. Their parents were also invited to participate. Participant experiences and views relating to the PT process were explored. Inductive thematic analysis was used to elicit a deep understanding of the experiences and needs of this cohort. Nineteen predictively tested young people were interviewed (8 tested for ICM, 11 for LQTS; of these, 11 were gene-positive) as well as 15 parents. Three intersecting themes were identified: ‘it’s a family affair’ (impact of/on family relationships and experience of the condition); ‘post-test day-to-day implications’ (impact of integrating gene-status on self-perception); and ‘needing developmentally-appropriate intervention and support’ (recognising the evolving needs of the young person as an individual and within their family unit). Young people, regardless of their gene status, require individualised support and follow-up. Family structure and experience influences perception and understanding of the PT process, highlighting the need to appropriately involve, support and educate all family members.

Repeated exposure to challenging clinical situations impacts healthcare professionals' well-being. Genetic counselors assist individuals to understand and adapt to difficult medical information, which often has implications for close family members. In the cardiac setting, managing families with profound grief and trauma following sudden cardiac death can be difficult, with potential for burnout and compassion fatigue. The aim of this study was to explore the impact of cardiovascular genetic counseling practice on genetic counselor well-being and describe self-care practices. Participants were recruited through the Australasian Society of Genetic Counselors. Semi-structured interviews explored challenges in cardiovascular genetic counseling practice, supervision, and self-care. Interview transcripts were analyzed using reflexive thematic analysis. Self-reported demographics, psychological well-being, and burnout measures were used. Eighteen genetic counselors participated. Median interview length was 54 min (range 40-74). All participants were female and 83% of European ethnicity. Few reported mild or moderate depression symptoms (17%), mild or moderate anxiety symptoms (22%), and none (0%) had scores indicating stress. Three (17%) had scores indicating burnout. Reflexive thematic analysis generated three themes: (1) cardiovascular genetic counseling is different, not harder or easier; (2) workplace pressures affect well-being; (3) a self-care "tool kit" is necessary and supervision is a key component. Genetic counseling practice and workload can affect well-being. A genetic counselor self-care 'tool kit' that includes supervision helps maintain well-being.

PURPOSE:The Australian Genomics Cardiovascular Disorders Flagship investigated genome sequencing as a first-line genetic test in 600 individuals with cardiomyopathy, primary arrhythmia syndromes, or congenital heart disease. Analysis of disease-specific virtual gene panels achieved a genetic diagnosis in 38% of participants. We sought to increase genetic diagnosis yields by analyzing lesser-evidenced disease genes, the mitochondrial genome, and by functional analysis of predicted splice-altering variants. METHODS:Genome sequences of 520 participants with cardiomyopathy or primary arrhythmia syndromes were reanalyzed in 572 cardiac genes and the mitochondrial genome. Participants with congenital heart disease were excluded. Variants predicted in silico to disrupt splicing were assessed with blood RNA and minigenes. RESULTS:A new genetic diagnosis was achieved in 4% (19/520) of participants, including deep intronic and mitochondrial genome variants. Ten participants had diagnostic variants in lesser evidenced disease genes; 9 had splicing variant pathogenicity functionally validated. Eleven participants had a newly identified variant of uncertain significance with high suspicion of pathogenicity, warranting clinical review. Our data supported the gene-disease association of 1 new cardiomyopathy gene, TBX20. CONCLUSION:Identifying new gene-disease relationships, maintaining contemporary gene panels, and integrating functional studies to refine splicing variant classifications increase genetic diagnoses for cardiomyopathies and primary arrhythmia syndromes.

Purpose: Families of children in pediatric acute care who are offered ultrarapid genomic sequencing are making complex decisions during a high-stress period. To reduce complexity for families and clinicians, we offered genomic screening for the child and parents after the completion of diagnostic testing. We evaluated uptake, understanding, and service delivery preferences. Methods: A cohort of 235 families who had completed ultrarapid diagnostic genomic sequencing at 17 Australian hospitals were offered up to 3 screens on their genomic data: pediatric-onset, adult-onset, and expanded couple carrier screening. We investigated decision making, understanding, and service delivery preferences using surveys at 3 time points (pre counseling, post counseling, and post result) and performed inductive content analysis of pretest genetic counseling transcripts. Results: A total of 119 families (51%) attended genetic counseling with 115 (49%) accepting genomic screening. Survey respondents were more likely to fi nd decisions about couple carrier screening easy (87%) compared with adult (68%; P = .002) or pediatric (71%; P = .01) screening decisions. All respondents with newly detected pathogenic variants accurately recalled this 1 month later. A delayed offer of screening was acceptable to most respondents (78%). Conclusion: Separating genomic screening from the stressful diagnostic period is supported by families who demonstrate good knowledge and recall. Our results suggest delaying genomic screening should be trialed more widely. (c) 2024 The Authors. Published by Elsevier Inc. on behalf of American College of Medical Genetics and Genomics. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

BACKGROUND AND AIMS:Truncating variants in the TTN gene (TTNtv) are the most common genetic cause of dilated cardiomyopathy (DCM) but also occur as incidental findings in the general population. This study investigated factors associated with the clinical manifestation of TTNtv. METHODS:An international multicentre retrospective observational study was performed in families with TTNtv-related DCM. Shared frailty models were used to estimate associations of variant characteristics with lifetime risk of DCM, and logistic regression to estimate odds ratios (ORs) for individual-level clinical risk factor profiles (cardiac conditions, cardiovascular comorbidities, lifestyle) and DCM. RESULTS:A total of 3158 subjects in 1043 families with TTNtv-related DCM were studied. TTNtv-positive subjects were 21-fold more likely to develop DCM [OR, 21.21; 95% confidence interval (CI), 14.80-30.39]. Disease onset was earlier in males, but was similar for TTNtv of different types and locations. The presence of clinical risk factors was associated with earlier DCM onset (OR, 3.41; 95% CI, 2.06-5.64), with a prior history of atrial fibrillation having a two-fold increased odds of DCM (OR, 2.05; 95% CI, 1.27-3.32). The prevalence of clinical risk factors increased with age; however, the strength of the DCM association was greatest for young-onset (<30 years) disease (OR, 4.75; 95% CI, 2.35-9.60). Administration of beta-adrenergic receptor or renin-angiotensin system-blocking drugs prior to overt DCM was associated with 87% reduced odds of DCM (OR, .13; 95% CI, .08-.23). CONCLUSIONS:Disease onset in TTNtv-associated familial DCM is dependent on individual patient context and is potentially modifiable by risk factor management and prophylactic therapeutic intervention.

PURPOSE:To develop and evaluate a scalable national program to build confidence, competence and capability in the use of rapid genomic testing (rGT) in the acute pediatric setting. METHODS:We used theory-informed approaches to design a modular, adaptive program of blended learning aimed at diverse professional groups involved in acute pediatric care. The program comprised 4 online learning modules and an online workshop and was centered on case-based learning. We evaluated the program using the Kirkpatrick 4-level model of training evaluation and report our findings using the Reporting Item Standards for Education and its Evaluation (RISE2) guidelines for genomics education and evaluation. RESULTS:Two hundred and two participants engaged with at least 1 component of the program. Participants self-reported increased confidence in using rGT, (P < .001), and quiz responses objectively demonstrated increased competence (eg, correct responses to a question on pretest counseling increased from 30% to 64%; P < .001). Additionally, their capability in applying genomic principles to simulated clinical cases increased (P < .001), as did their desire to take on more responsibility for performing rGT. The clinical interpretation of more complex test results (such as negative results or variants of uncertain significance) appeared to be more challenging, indicating a need for targeted education in this area. CONCLUSION:The program format was effective in delivering multidisciplinary and wide-scale genomics education in the acute care context. The modular approach we have developed now lends itself to application in other medical specialties or areas of health care.

TBX20 encodes a cardiac transcription factor that is associated with atrial septal defects. Recent studies implicate loss-of-function TBX20 variants with left ventricular non-compaction cardiomyopathy (LVNC), although clinical and genetic data in families are limited. We report four families with TBX20 loss-of-function variants that segregate with LVNC. Genetic testing using genome or exome sequencing was performed in index cases, variants were validated with Sanger sequencing, and cascade genetic testing was performed in family members. A multi-exon deletion, small deletion, essential splice site variant and nonsense variant in TBX20 were found in four families. The index cases in two families were symptomatic children with identical congenital heart diseases and LVNC who developed different cardiomyopathy phenotypes with one developing heart failure requiring transplantation. In another family, the child index case had LVNC and congestive heart failure requiring heart transplantation. In the fourth family, the index case was a symptomatic adult with LVNC. In all families, the variants segregated in relatives with isolated LVNC, or with congenital heart disease or cardiomyopathy. Family members displayed a clinical spectrum from asymptomatic to severe presentations including heart failure. Our data strengthen TBX20 loss-of-function variants as a rare cause of LVNC and support TBX20 inclusion in genetic testing of LVNC.

PURPOSE:Gene selection for genomic newborn screening (gNBS) underpins the validity, acceptability, and ethical application of this technology. Existing gNBS gene lists are highly variable despite being based on shared principles of gene-disease validity, treatability, and age of onset. This study aimed to curate a gNBS gene list that builds upon existing efforts and provide a core consensus list of gene-disease pairs assessed by multiple expert groups worldwide. METHODS:Our multidisciplinary expert team curated a gene list using an open platform and multiple existing curated resources. We included severe treatable disorders with age of disease onset <5 years with established gene-disease associations and reliable variant detection. We compared the final list with published lists from 5 other gNBS projects to determine consensus genes and to identify areas of discrepancy. RESULTS:We reviewed 1279 genes and 604 met our inclusion criteria. Metabolic conditions comprised the largest group (25%), followed by immunodeficiencies (21%) and endocrine disorders (15%). We identified 55 consensus genes included by all 6 gNBS research projects. Common reasons for discrepancy included variable definitions of treatability and strength of gene-disease association. CONCLUSION:We have identified a consensus gene list for gNBS that can be used as a basis for systematic harmonization efforts internationally.

Introduction As routine genomic testing expands, so too does the opportunity to look for additional health information unrelated to the original reason for testing, termed additional findings (AF). Analysis for many different types of AF may be available, particularly to families undergoing trio genomic testing. The optimal model for service delivery remains to be determined, especially when the original test occurs in the acute care setting. Methods and analysis Families enrolled in a national study providing ultrarapid genomic testing to critically ill children will be offered analysis for three types of AF on their stored genomic data: paediatric-onset conditions in the child, adult-onset conditions in each parent and reproductive carrier screening for the parents as a couple. The offer will be made 3–6 months after diagnostic testing. Parents will have access to a modified version of the Genetics Adviser web-based decision support tool before attending a genetic counselling appointment to discuss consent for AF. Parental experiences will be evaluated using qualitative and quantitative methods on data collected through surveys, appointment recordings and interviews at multiple time points. Evaluation will focus on parental preferences, uptake, decision support use and understanding of AF. Genetic health professionals’ perspectives on acceptability and feasibility of AF will also be captured through surveys and interviews. Ethics and dissemination This project received ethics approval from the Melbourne Health Human Research Ethics Committee as part of the Australian Genomics Health Alliance protocol: HREC/16/MH/251. Findings will be disseminated through peer-review journal articles and at conferences nationally and internationally.

There is an incomplete understanding of the burden of splice-disrupting variants in definitively associated inherited heart disease genes and whether these genes can amplify from blood RNA to support functional confirmation of splicing outcomes. We performed burden testing of rare splice-disrupting variants in people with inherited heart disease and sudden unexplained death compared to 125,748 population controls. ClinGen definitively disease-associated inherited heart disease genes were amplified using RNA extracted from fresh blood, derived cardiomyocytes, and myectomy tissue. Variants were functionally assessed and classified for pathogenicity. We found 88 in silico-predicted splice-disrupting variants in 128 out of 1242 (10.3%) unrelated participants. There was an excess burden of splice-disrupting variants in PKP2 (5.9%), FLNC (2.7%), TTN (2.8%), MYBPC3 (8.2%) and MYH7 (1.3%), in distinct cardiomyopathy subtypes, and KCNQ1 (3.6%) in long QT syndrome. Blood RNA supported the amplification of 21 out of 31 definitive disease-associated inherited heart disease genes. Our functional studies confirmed altered splicing in six variants. Eleven variants of uncertain significance were reclassified as likely pathogenic based on functional studies and six were used for cascade genetic testing in 12 family members. Our study highlights that splice-disrupting variants are a significant cause of inherited heart disease, and that analysis of blood RNA confirms splicing outcomes and supports variant pathogenicity classification.

American College of Medical Genetics and Genomics–Association of Molecular Pathology (ACMG/AMP) variant classification guidelines often consider splicing variants as variants of uncertain significance (VUS), due to a lack of data to demonstrate mis-splicing. This disproportionately affects genes with a predominance of splicing variants, such as LAMP2-associated Danon disease (Online Mendelian Inheritance in Man [OMIM] #300257), where up to 35% of reported variants affect splicing. We present a family with hypertrophic cardiomyopathy (HCM) where a LAMP2 splicing VUS was reclassified following familial segregation and RNA diagnostics.

The VicDFI collaboration (Royal Melbourne (RMH) and Royal Children's (RCH) Hospitals) undertook creation of a family-based database for shared use.