Impact of a Genetic Diagnosis of a Mitochondrial Disorder 5–17 Years After the Death of an Affected Child

Cascade testing in mitochondrial diseases: a cross-sectional retrospective study

BACKGROUND

Cascade testing can offer improved surveillance and timely introduction of clinical management for the at-risk biological relatives. Data on cascade testing and costs in mitochondrial diseases are lacking. To address this gap, we performed a cross-sectional retrospective study to provide a framework for cascade testing in mitochondrial diseases, to estimate the eligibility versus real-time uptake of cascade testing and to evaluate the cost of the genetic diagnosis of index cases and the cost of predictive cascade testing.

METHODS

Data was collected through retrospective chart review. The variant inheritance pattern guided the identification of eligible first-degree relatives: (i) Males with mitochondrial DNA (mtDNA) single nucleotide variants (SNVs) - siblings and mothers. (ii) Females with mtDNA SNVs - siblings, mothers and offspring. (iii) Autosomal Dominant (AD) nuclear DNA (nDNA) variants - siblings, offspring and both parents. (iv) Autosomal Recessive (AR) nDNA variants - siblings.

RESULTS

We recruited 99 participants from the Adult Mitochondrial Disease Clinic in Sydney. The uptake of cascade testing was 55.2% in the mtDNA group, 55.8% in the AD nDNA group and 0% in AR nDNA group. Of the relatives in mtDNA group who underwent cascade testing, 65.4% were symptomatic, 20.5% were oligosymptomatic and 14.1% were asymptomatic. The mean cost of cascade testing for eligible first-degree relatives (mtDNA group: $694.7; AD nDNA group: $899.1) was lower than the corresponding index case (mtDNA group: $4578.4; AD nDNA group: $5715.1) (p < 0.001).

CONCLUSION

The demand for cascade testing in mitochondrial diseases varies according to the genotype and inheritance pattern. The real-time uptake of cascade testing can be influenced by multiple factors. Early diagnosis of at-risk biological relatives of index cases through cascade testing, confirms the diagnosis in those who are symptomatic and facilitates implementation of surveillance strategies and clinical care at an early stage of the disease.

Searching for a sense of closure: parental experiences of recontacting after a terminated pregnancy for congenital malformations

Rapid advances in genetic testing have improved the probability of successful genetic diagnosis. For couples who undergo a termination of pregnancy (TOP) due to foetal congenital malformations, these techniques may reveal the underlying cause and satisfy parents' need to know. The aim of this qualitative descriptive research study was to explore couples' experience of being recontacted after a congenital malformation-related TOP, as well as their reasons for participation. A retrospective cohort of 31 eligible candidates was recontacted for additional genetic testing using a standardized letter followed by a telephone call. Fourteen participants (45%) were included. Data were collected through semi-structured interviews at a hospital genetics department (UZ Brussel). Interviews were audiotaped, transcribed and analysed using thematic analysis. We found that despite the sometimes considerable length of time that passed since TOP, participants were still interested in new genetic testing. They appreciated that the initiative originated from the medical team, describing it as a "sensitive" approach. Both intrinsic (providing answers for themselves and their children) and extrinsic motivators (contributing to science and helping other parents) were identified as important factors for participation. These results show that participants often remain interested in being recontacted for new genetic testing such as whole genome sequencing, even after several years. As such, the results of this study can offer guidance in the more general current debate on recontacting patients in the field of genetics.

Ending an Odyssey? The Psychosocial Experiences of Parents after the Genetic Diagnosis of a Mitochondrial Disease in Children

Obtaining a genetic diagnosis of a primary mitochondrial disease (PMD) is often framed as a diagnostic odyssey. Yet, even after receiving a diagnosis, parents of affected children experience ongoing therapeutic and prognostic uncertainty and considerable psychosocial challenges. Semi-structured interviews (N = 24) were conducted with parents of 13 children (aged 2-19 years) with a genetically confirmed PMD. Paternal (N = 11) and maternal (N = 13) perspectives were obtained, and thematic analysis was performed on all interviews. A genetic diagnosis was valuable and empowering for parents, despite eliciting varied emotional responses. While the diagnosis helped focus management decisions, families often felt overwhelmed and unsupported in navigating the healthcare system. Most parents reported a serious impact on their romantic relationship. The sources of social support varied, with a preference for established friendship and family support networks over disease-specific community support groups. Most parents favored prenatal genetic testing in the event of a future pregnancy. This study provides insight into the lived experiences of parents after a genetic diagnosis of PMD in their children. The findings draw awareness to supportive care needs and highlight important gaps that should be addressed to ensure that parents feel supported within a holistic framework of management for PMDs.

Strategies to Uplift Novel Mendelian Gene Discovery for Improved Clinical Outcomes

Rare genetic disorders, while individually rare, are collectively common. They represent some of the most severe disorders affecting patients worldwide with significant morbidity and mortality. Over the last decade, advances in genomic methods have significantly uplifted diagnostic rates for patients and facilitated novel and targeted therapies. However, many patients with rare genetic disorders still remain undiagnosed as the genetic etiology of only a proportion of Mendelian conditions has been discovered to date. This article explores existing strategies to identify novel Mendelian genes and how these discoveries impact clinical care and therapeutics. We discuss the importance of data sharing, phenotype-driven approaches, patient-led approaches, utilization of large-scale genomic sequencing projects, constraint-based methods, integration of multi-omics data, and gene-to-patient methods. We further consider the health economic advantages of novel gene discovery and speculate on potential future methods for improved clinical outcomes.

Stakeholders' perspectives on the post-mortem use of genetic and health-related data for research: a systematic review

The majority of biobank policies and consent forms do not address post-mortem use of data for medical research, thus causing uncertainty after research participants' death. This systematic review identifies studies examining stakeholders' perspectives on this issue. We conducted a search in MEDLINE, CINAHL, EMBASE and Web of Science. Findings were categorised in two themes: (1) views on the use of data for medical research after participants' death, and (2) perspectives regarding the post-mortem return of individual genetic research results. An important subtheme was the appropriate authority and degree of control over posthumous use of data. The sixteen included studies all focused on genetic data and used quantitative and qualitative methods to survey perspectives of research participants, family members, researchers and Institutional Review Board members. Acceptability of post-mortem use of data for medical research was high among research participants and their relatives. Most stakeholders thought participants should be informed about post-mortem research uses during initial consent. Between lay persons and professionals, disagreement exists about whether relatives should receive actionable genetic findings, and whether the deceased's previous preferences can be overridden. We conclude that regulations and ethical guidance should leave room for post-mortem use of personal data for research, provided that informed consent procedures are transparent on this issue, including the return of individual research findings to relatives. Future research is needed to explore underlying causes for differences in views, as well as ethical and legal issues on the appropriate level of control by deceased research participants (while alive) and their relatives.

Men's experiences of recontact about a potential increased risk of prostate cancer due to Lynch Syndrome: "Just another straw on the stack"

The practice of recontacting patients to provide new health information is becoming increasingly common in clinical genetics, despite the limited research to evidence the patient experience. We explored how men with Lynch Syndrome (LS) understand and experience being recontacted about a potential increased risk of prostate cancer. Sixteen men with LS (Meanage 51 years) were recruited from an Australian screening study to undergo a semi-structured interview. A modified grounded theory approach was used to guide data collection and thematic analysis. Qualitative coding was shared by the research team to triangulate analysis. The practice of recontact was viewed by participants as acceptable and was associated with minimal emotional distress. The majority of men understood that they may be above population risk of prostate cancer, although evidence was still emerging. Men reported high engagement with personal and familial health, including regular screening practices and familial risk communication. Findings suggest that men's carrier status and beliefs about the actionability of the new cancer risk information influence their response to recontact. Recontact practices that include the offer of risk management strategies may lead to improved patient outcomes (e.g., reduced cancer worry and increased health engagement), if perceived as valuable by recipients.

Recontacting or not recontacting? A survey of current practices in clinical genetics centres in Europe

Advances in genomic medicine are improving diagnosis and treatment of some health conditions, and the question of whether former patients should be recontacted is therefore timely. The issue of recontacting is becoming more important with increased integration of genomics in 'mainstream' medicine. Empirical evidence is needed to advance the discussion over whether and how recontacting should be implemented. We administered a web-based survey to genetic services in European countries to collect information about existing infrastructures and practices relevant to recontacting patients. The majority of the centres stated they had recontacted patients to update them about new significant information; however, there were no standardised practices or systems in place. There was also a multiplicity of understandings of the term 'recontacting', which respondents conflated with routine follow-up programmes, or even with post-test counselling. Participants thought that recontacting systems should be implemented to provide the best service to the patients and families. Nevertheless, many barriers to implementation were mentioned. These included: lack of resources and infrastructure, concerns about potential negative psychological consequences of recontacting, unclear operational definitions of recontacting, policies that prevent healthcare professionals from recontacting, and difficulties in locating patients after their last contact. These barriers are also intensified by the highly variable development (and establishment) of the specialties of medical genetics and genetic counselling across different European countries. Future recommendations about recontacting need to consider these barriers. It is also important to reach an 'operational definition' that can be useful in different countries.

Recontacting in light of new genetic diagnostic techniques for patients with intellectual disability: Feasibility and parental perspectives

A higher diagnostic yield from new diagnostic techniques makes re-evaluation in patients with intellectual disability without a causal diagnosis valuable, and is currently only performed after new referral. Active recontacting might serve a larger group of patients. We aimed to evaluate parental perspectives regarding recontacting and its feasibility in clinical genetic practice. A recontacting pilot was performed in two cohorts of children with intellectual disability. In cohort A, parents were recontacted by phone and in cohort B by letter, to invite them for a re-evaluation due to the new technologies (array CGH and exome sequencing, respectively). Parental opinions, preferences and experiences with recontacting were assessed by a self-administered questionnaire, and the feasibility of this pilot was evaluated. 47 of 114 questionnaires were returned. In total, 87% of the parents believed that all parents should be recontacted in light of new insights, 17% experienced an (positive or negative) emotional reaction. In cohort A, approached by phone, 36% made a new appointment for re-evaluation, and in cohort B, approached by letter, 4% did. Most parents have positive opinions on recontacting. Recontacting might evoke emotional responses that may need attention. Recontacting is feasible but time-consuming and a large additional responsibility for clinical geneticists.

A 'joint venture' model of recontacting in clinical genomics: challenges for responsible implementation

Advances in genomics often lead healthcare professionals (HCPs) to learn new information, e.g., about reinterpreted variants that could have clinical significance for patients seen previously. A question arises of whether HCPs should recontact these former patients. We present some findings interrogating the views of patients (or parents of patients) with a rare or undiagnosed condition about how such recontacting might be organised ethically and practically. Forty-one interviews were analysed thematically. Participants suggested a 'joint venture' model in which efforts to recontact are shared with HCPs. Some proposed an ICT-approach involving an electronic health record that automatically alerts them to potentially relevant updates. The need for rigorous privacy controls and transparency about who could access their data was emphasised. Importantly, these findings highlight that the lack of clarity about recontacting is a symptom of a wider problem: the lack of necessary infrastructure to pool genomic data responsibly, to aggregate it with other health data, and to enable patients/parents to receive updates. We hope that our findings will instigate a debate about the way responsibilities for recontacting under any joint venture model could be allocated, as well as the limitations and normative implications of using ICT as a solution to this intractable problem. As a first step to delineating responsibilities in the clinical setting, we suggest HCPs should routinely discuss recontacting with patients/parents, including the new information that should trigger a HCP to initiate recontact, as part of the consent process for genetic testing.

Mitochondrial diseases

Mitochondrial diseases are a group of genetic disorders that are characterized by defects in oxidative phosphorylation and caused by mutations in genes in the nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) that encode structural mitochondrial proteins or proteins involved in mitochondrial function. Mitochondrial diseases are the most common group of inherited metabolic disorders and are among the most common forms of inherited neurological disorders. One of the challenges of mitochondrial diseases is the marked clinical variation seen in patients, which can delay diagnosis. However, advances in next-generation sequencing techniques have substantially improved diagnosis, particularly in children. Establishing a genetic diagnosis allows patients with mitochondrial diseases to have reproductive options, but this is more challenging for women with pathogenetic mtDNA mutations that are strictly maternally inherited. Recent advances in in vitro fertilization techniques, including mitochondrial donation, will offer a better reproductive choice for these women in the future. The treatment of patients with mitochondrial diseases remains a challenge, but guidelines are available to manage the complications of disease. Moreover, an increasing number of therapeutic options are being considered, and with the development of large cohorts of patients and biomarkers, several clinical trials are in progress.

Recontact in clinical practice: a survey of clinical genetics services in the United Kingdom

PURPOSE

To ascertain whether and how recontacting occurs in the United Kingdom.

METHOD

A Web-based survey was administered online between October 2014 and July 2015. A link to the survey was circulated via an e-mail invitation to the clinical leads of the United Kingdom's 23 clinical genetics services, with follow-up with senior clinical genetics staff.

RESULTS

The majority of UK services reported that they recontact patients and their family members. However, recontacting generally occurs in an ad hoc fashion when an unplanned event causes clinicians to review a file (a "trigger"). There are no standardized recontacting practices in the United Kingdom. More than half of the services were unsure whether formalized recontacting systems should be implemented. Some suggested greater patient involvement in the process of recontacting.

CONCLUSION

This research suggests that a thorough evaluation of the efficacy and sustainability of potential recontacting systems within the National Health Service would be necessary before deciding whether and how to implement such a service or to create guidelines on best-practice models.Genet Med 18 9, 876-881.

Timing and context: important considerations in the return of genetic results to research participants

General consensus exists that clinically significant germline genetic research results should be fed back to research participants. A body of literature is emerging about Australian research participants' experiences of feedback of genetic research results and factors that influence a participant's actions after receiving such information. This exploratory qualitative study conducted interviews with 11 participants from the International Sarcoma Kindred Study, four probands and seven of their relatives. They had been informed by letter of the availability of clinically significant germline TP53 mutations identified through research. We examined the participants' views about the feedback of these genetic test results. Thematic (inductive) analysis was used to analyse the data. A number of factors influenced participants' responses following notification. This included participants' understanding of the notification letter and their perception of the relevance of the information for them and/or their family. Most notably, timing of the letter in the context of an individual's current life experiences was important. Timing and context are novel factors identified that may impact on research participants' understanding or their ability to access clinically significant research results. We outline strategies for disseminating results to research participants and their next of kin that may reduce their uncertainty around the receipt of research results.

Is there a duty to recontact in light of new genetic technologies? A systematic review of the literature

PURPOSE

With rapid advances in genetic technologies, new genetic information becomes available much faster today than just a few years ago. This has raised questions about whether clinicians have a duty to recontact eligible patients when new genetic information becomes available and, if such duties exist, how they might be implemented in practice.

METHODS

We report the results of a systematic literature search on the ethical, legal, social (including psychological), and practical issues involved in recontacting former patients who received genetic services. We identified 1,428 articles, of which 61 are covered in this review.

RESULTS

The empirical evidence available indicates that most but not all patients value being recontacted. A minority of (older) articles conclude that recontacting should be a legal duty. Most authors consider recontacting to be ethically desirable but practically unfeasible. Various solutions to overcome these practical barriers have been proposed, involving efforts of laboratories, clinicians, and patients.

CONCLUSION

To advance the discussion on implementing recontacting in clinical genetics, we suggest focusing on the question of in what situations recontacting might be regarded as good standard of care. To this end, reaching a professional consensus, obtaining more extensive empirical evidence, and developing professional guidelines are important.

Mitochondrial disease: a challenge for the caregiver, the family, and society

Mitochondrial diseases represent a genetically and clinically heterogeneous group of inherited metabolic disorders, often resulting in poor functional and survival outcomes for the patient and considerable psychosocial distress for the caregiver. The systematic review undertaken in the present paper emphasizes the critical role of the caregiver in the management of a child with mitochondrial disease, with focus on the burden of mitochondrial disease on the caregiver, the family, and society.