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Abstract The KidGen Collaborative's Policy Implementation Workshop 2023 celebrated the 10th anniversary of Australia's first kidney genetics clinic in Brisbane. This event marked the establishment of a national network now comprising 19 kidney genetics clinics across Australia, all dedicated to providing equitable access to genomic testing for families affected by genetic kidney diseases. The workshop reflected on past progress and outlined future objectives for kidney genetics in Australia, recognising the collaborative efforts of clinical teams, researchers, and patients. Key insights from the workshop are documented in the proceedings.

Abstract Background Diabetes presenting in young adults is often challenging to classify. Diabetic ketoacidosis is typically seen in autoimmune type 1 diabetes mellitus and more rarely in young onset type 2 diabetes mellitus. Beta-ketothiolase deficiency (BKD) is a rare autosomal recessive condition affecting isoleucine catabolism and ketone body metabolism. BKD typically manifests in childhood as recurrent episodes of ketoacidosis, the frequency of which tends to reduce with age. There is a paucity of data with respect to the co-existence of persistent dysglycemia with BKD. Case presentation and literature review We present a novel case of diabetes presenting as diabetic ketoacidosis in a 34-year-old man with BKD, with genetically confirmed compound heterozygosity for variants in ACAT1, including a novel ACAT1 c.481T>C, p.(Tyr161His) variant. Diabetes in people with BKD presents unique diagnostic and management challenges. To further contextualize our findings, we conducted a comprehensive narrative review of the existing literature with respect to dysglycemia in those with BKD, especially in adulthood. There are no existing reports describing diabetes in adults with BKD. Stress hyperglycemia is not uncommon when children with BKD are acutely unwell, with several pediatric case reports describing short-lived hyperglycemia but normal HbA1c measurements during metabolic crises (indicating the absence of persistent hyperglycemia). Conclusions This is the first report of diabetic ketoacidosis in an adult with BKD, with an elevated HbA1c consistent with persistent hyperglycemia. This case highlights the importance of checking HbA1c in people with BKD and hyperglycemia in order to uncover potential coexisting diabetes, facilitating timely management and preventing complications. Increased reporting on the longitudinal outcomes of those with rare metabolic disorders is essential for identifying potential associations with conditions like diabetes.

Abstract Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic cause of kidney failure and is primarily associated with PKD1 or PKD2. Approximately 10% of patients remain undiagnosed after standard genetic testing. We aimed to utilise short and long-read genome sequencing and RNA studies to investigate undiagnosed families. Patients with typical ADPKD phenotype and undiagnosed after genetic diagnostics were recruited. Probands underwent short-read genome sequencing, PKD1 and PKD2 coding and non-coding analyses and then genome-wide analysis. Targeted RNA studies investigated variants suspected to impact splicing. Those undiagnosed then underwent Oxford Nanopore Technologies long-read genome sequencing. From over 172 probands, 9 met inclusion criteria and consented. A genetic diagnosis was made in 8 of 9 (89%) families undiagnosed on prior genetic testing. Six had variants impacting splicing, five in non-coding regions of PKD1. Short-read genome sequencing identified novel branchpoint, AG-exclusion zone and missense variants generating cryptic splice sites and a deletion causing critical intron shortening. Long-read sequencing confirmed the diagnosis in one family. Most undiagnosed families with typical ADPKD have splice-impacting variants in PKD1. We describe a pragmatic method for diagnostic laboratories to assess PKD1 and PKD2 non-coding regions and validate suspected splicing variants through targeted RNA studies.

Purpose: The Australian Genomics Cardiovascular Disorders Flagship was a national multidisciplinary collaboration. It aimed to investigate the feasibility of genome sequencing (GS) and functional genomics to resolve variants of uncertain significance (VUS) in the clinical management of patients and families with cardiomyopathies, primary arrhythmias, and congenital heart disease (CHD). Methods: Between April 2019 and December 2021, 600 probands meeting cardiovascular disorder criteria from 17 cardiology and genetics clinics across Australia were enrolled in the Flagship and underwent GS. The Flagship adopted a tiered approach to GS analysis. Tier 1 analysis assessed genes with established clinical validity for each cardiovascular condition. Tier 2 analysis assessed lesser-evidenced research-based genes. Tier 3 analysis assessed the functional impact of VUS that remained after tier 1 and tier 2 analysis. Results: Overall, a pathogenic or likely pathogenic variant was identified in 41% of participants with a cardiomyopathy, 40% with an arrhythmia syndrome, and 15% with a familial CHD/CHD+Extra Cardiac Anomalies. A VUS outcome ranged from 13% for arrhythmias to 34% for CHD/CHD+Extra Cardiac Anomalies participants. Tier 2 research analysis identified a likely pathogenic/pathogenic variant for a further 15 participants and a VUS for an additional 15 participants. Conclusion: The Flagship successfully facilitated a model of care that harnesses clinical GS and functional genomics for the resolution of VUS in the clinical setting. This valuable data set can be used to inform clinical practice and facilitate research into the future.

Abstract Predicting the impact of coding and noncoding variants on splicing is challenging, particularly in non-canonical splice sites, leading to missed diagnoses in patients. Existing splice prediction tools are complementary but knowing which to use for each splicing context remains difficult. Here, we describe Introme, which uses machine learning to integrate predictions from several splice detection tools, additional splicing rules, and gene architecture features to comprehensively evaluate the likelihood of a variant impacting splicing. Through extensive benchmarking across 21,000 splice-altering variants, Introme outperformed all tools (auPRC: 0.98) for the detection of clinically significant splice variants. Introme is available at https://github.com/CCICB/introme .

Abstract Genetic testing in nephrology clinical practice has moved rapidly from a rare specialized test to routine practice both in pediatric and adult nephrology. However, clear information pertaining to the likely outcome of testing is still missing. Here we describe the experience of the accredited Australia and New Zealand Renal Gene Panels clinical service, reporting on sequencing for 552 individuals from 542 families with suspected kidney disease in Australia and New Zealand. An increasing number of referrals have been processed since service inception with an overall diagnostic rate of 35%. The likelihood of identifying a causative variant varies according to both age at referral and gene panel. Although results from high throughput genetic testing have been primarily for diagnostic purposes, they will increasingly play an important role in directing treatment, genetic counseling, and family planning.

Introduction: Genomic testing is becoming widely available as a diagnostic tool, although widespread implementation is not yet established in nephrology. Methods: An anonymous electronic survey was administered to investigate experience and confidence with genomic tests, perceived clinical utility of genomic services, preferences for service delivery models, and readiness for implementation among nephrologists. Questions were guided by a comprehensive literature review and published tools, including a validated theoretical framework for implementation of genomic medicine: Consolidated Framework for Implementation Research (CFIR). Results: Responses were received from 224 clinicians, of which 172 were eligible for analysis. Most clinicians (132 [76%]) had referred at least one patient to a genetics clinic. Despite most clinicians (136 [85%]) indicating that they believed genetic testing would be useful, only 39 (23%) indicated they felt confident to use results of genomic testing, with pediatric clinicians feeling more confident compared with adult clinicians (12 of 20 [60%] vs. 27 of 149 [18%]), P < 0.01, Fisher exact). A multidisciplinary renal genetics clinic was the preferred model among clinicians surveyed (98 of 172 [57%]). A key implementation barrier highlighted related to the hospital or organizational culture and/or environment. Specific barriers noted in quantitative and qualitative responses included inadequate staffing, learning resources, and funding. Conclusions: Our findings suggest support for genomic testing among nephrologists, with a strong preference for a multidisciplinary model (involving a nephrologist, clinical geneticist, and genetic counselor). Broad-ranging interventions are urgently required to shift the current culture and ensure successful implementation of genomics in nephrology, including reducing knowledge gaps, increased funding and resources, disease-specific guidelines, and streamlining of testing processes.

Early identification of genetic kidney disease allows personalised management, clarification of risk for relatives, and guidance for family planning. Genetic disease is underdiagnosed, and recognition of genetic disease is particularly challenging in patients with kidney failure without distinguishing diagnostic features. To address this challenge, the primary aim of this study is to determine the proportion of genetic diagnoses amongst patients with kidney failure of unknown aetiology, using whole genome sequencing (WGS). A cohort of up to 100 Australian patients with kidney failure of unknown aetiology, with onset

Introduction Recent advances in genomic technology have allowed better delineation of renal conditions, the identification of new kidney disease genes and subsequent targets for therapy. To date, however, the utility of genomic testing in a clinically ascertained, prospectively recruited kidney disease cohort remains unknown. The aim of this study is to explore the clinical utility and cost-effectiveness of genomic testing within a national cohort of patients with suspected genetic kidney disease who attend multidisciplinary renal genetics clinics.Methods and analysis This is a prospective observational cohort study performed at 16 centres throughout Australia. Patients will be included if they are referred to one of the multidisciplinary renal genetics clinics and are deemed likely to have a genetic basis to their kidney disease by the multidisciplinary renal genetics team. The expected cohort consists of 360 adult and paediatric patients recruited by December 2018 with ongoing validation cohort of 140 patients who will be recruited until June 2020. The primary outcome will be the proportion of patients who receive a molecular diagnosis via genomic testing (diagnostic rate) compared with usual care. Secondary outcomes will include change in clinical diagnosis following genomic testing, change in clinical management following genomic testing and the cost-effectiveness of genomic testing compared with usual care.Ethics and dissemination The project has received ethics approval from the Melbourne Health Human Research Ethics Committee as part of the Australian Genomics Health Alliance protocol: HREC/16/MH/251. All participants will provide written informed consent for data collection and to undergo clinically relevant genetic/genomic testing. The results of this study will be published in peer-reviewed journals and will also be presented at national and international conferences.