Qualitative study of GPs' views and experiences of population-based preconception expanded carrier screening in the Netherlands: bioethical perspectives.

OBJECTIVE: Between 2016 and 2017, a population-based preconception expanded carrier screening (PECS) test was developed in the Netherlands during a pilot study. It was subsequently made possible in mid-2018 for couples to ask to have such a PECS test from specially trained general practitioners (GPs). Research has described GPs as crucial in offering PECS tests, but little is known about the GPs' views on PECS and their experiences of providing this test. This article presents a thematic analysis of the PECS practice from the perspective of GPs and a bioethical discussion of the empirical results. DESIGN: Empirical bioethics. A thematic analysis of qualitative semi-structured interviews was conducted, and is combined with an ethical/philosophical discussion. SETTING: The Netherlands. PARTICIPANTS: 7 Dutch GPs in the Netherlands, interviewed in 2019-2020. RESULTS: Two themes were identified in the thematic analysis: 'Choice and its complexity' and 'PECS as prompting existential concerns'. The empirical bioethics discussion showed that the first theme highlights that several areas coshape the complexity of choice on PECS, and the need for shared relational autonomous decision-making on these areas within the couple. The second theme highlights that it is not possible to analyse the existential issues raised by PECS solely on the level of the couple or family. A societal level must be included, since these levels affect each other. We refer to this as 'entangled existential genetics'. CONCLUSION: The empirical bioethical analysis leads us to present two practical implications. These are: (1) training of GPs who are to offer PECS should cover shared relational autonomous decision-making within the couple and (2) more attention should be given to existential issues evoked by genetic considerations, also during the education of GPs and in bioethical discussions around PECS.

A clinical perspective on ethical issues in genetic testing.

Genetic testing is traditionally preceded by counselling to discuss its advantages and disadvantages with individuals so they can make informed decisions. The new technique of whole genome or exome sequencing, which is currently only used in research settings, can identify many gene mutations, including substantial numbers of mutations with unknown pathological effect; it may, therefore, threaten this balanced approach if it is used in a clinical setting. We discuss the ethical challenges of several approaches to pre- and postnatal DNA testing, individual privacy versus the interests of families and of scientists, and the clinician's duty to re-contact if new information or options become available.

The sense and nonsense of direct-to-consumer genetic testing for cardiovascular disease.

Expectations are high that increasing knowledge of the genetic basis of cardiovascular disease will eventually lead to personalised medicine-to preventive and therapeutic interventions that are targeted to at-risk individuals on the basis of their genetic profiles. Most cardiovascular diseases are caused by a complex interplay of many genetic variants interacting with many non-genetic risk factors such as diet, exercise, smoking and alcohol consumption. Since several years, genetic susceptibility testing for cardiovascular diseases is being offered via the internet directly to consumers. We discuss five reasons why these tests are not useful, namely: (1) the predictive ability is still limited; (2) the risk models used by the companies are based on assumptions that have not been verified; (3) the predicted risks keep changing when new variants are discovered and added to the test; (4) the tests do not consider non-genetic factors in the prediction of cardiovascular disease risk; and (5) the test results will not change recommendations of preventive interventions. Predictive genetic testing for multifactorial forms of cardiovascular disease clearly lacks benefits for the public. Prevention of disease should therefore remain focused on family history and on non-genetic risk factors as diet and physical activity that can have the strongest impact on disease risk, regardless of genetic susceptibility.

Desmin-related myopathy.

Desmin-related myopathy (DRM) is an autosomally inherited skeletal and cardiac myopathy, mainly caused by dominant mutations in the desmin gene (DES). We provide (i) a literature review on DRM, including clinical manifestations, inheritance, molecular genetics, myopathology and management and (ii) a meta-analysis of reported DES mutation carriers, focusing on their clinical characteristics and potential genotype-phenotype correlations. Meta-analysis: DES mutation carriers (n = 159) with 40 different mutations were included. Neurological signs were present in 74% and cardiological signs in 74% of carriers (both neurological and cardiological signs in 49%, isolated neurological signs in 22%, and isolated cardiological signs in 22%). More than 70% of carriers exhibited myopathy or muscular weakness, with normal creatine kinase levels present in one third of them. Up to 50% of carriers had cardiomyopathy and around 60% had cardiac conduction disease or arrhythmias, with atrioventricular block as an important hallmark. Symptoms generally started during the 30s; a quarter of carriers died at a mean age of 49 years. Sudden cardiac death occurred in two patients with a pacemaker, suggesting a ventricular tachyarrhythmia as cause of death. The majority of DES mutations were missense mutations, mostly located in the 2B domain. Mutations in the 2B domain were predominant in patients with an isolated neurological phenotype, whereas head and tail domain mutations were predominant in patients with an isolated cardiological phenotype.

Haplotype sharing test maps genes for familial cardiomyopathies.

Identifying a mutation in a heterogeneous disease such as inherited cardiomyopathy is a challenge because classical methods, like linkage analysis, can often not be applied as there are too few meioses between affected individuals. However, if affected individuals share the same causal mutation, they will also share a genomic region surrounding it. High-density genotyping arrays are able to identify such regions shared among affected individuals. We hypothesize that the longest shared haplotype is most likely to contain the disease-causing mutation. We applied this method to two pedigrees: one with arrhythmogenic right ventricular cardiomyopathy (ARVC) and one with dilated cardiomyopathy (DCM), using high-density genome-wide SNP arrays. In the ARVC pedigree, the largest haplotype was on chromosome 12 and contained a causative PKP2 mutation. In the DCM pedigree, a causative MYH7 mutation was present on a large shared haplotype on chromosome 14. We calculated that a pedigree containing at least seven meioses has a high chance of correctly detecting the mutation-containing haplotype as the largest. Our data show that haplotype sharing analysis can assist in identifying causative genes in families with low penetrance Mendelian diseases, in which standard tools cannot be used due to lack of sufficient pedigree information.

Rationale and design of the CAREFUL study : The yield of CARdiogenetic scrEening in First degree relatives of sudden cardiac and UnexpLained death victims <45 years.

Background. Sudden cardiac death (SCD) in the young (1-45 years) is a strong risk factor for the presence of inherited cardiac diseases in surviving first-degree relatives. Postmortem investigation of the victim and cardiogenetic evaluation of the first-degree relatives is indicated to detect inherited cardiac diseases and treat relatives at an early stage to prevent SCD. In the Netherlands, postmortem investigation is often not performed and relatives of SCD and sudden unexplained death (SUD) victims are rarely evaluated for inherited cardiac diseases.Methods. A prospective population-based follow-up study carried out in two intervention regions and two control regions. In the intervention regions a comprehensive intervention (stimulate autopsy and storage of victims DNA and the referral of first-degree relatives for cardiogenetic evaluation) is applied in a 'top down' and 'bottom up' mode. In each region, young sudden death victims are registered and for all cases performance of autopsy and evaluation of relatives in a cardiogenetics outpatient clinic will be determined.Expected results. The study will provide information on the incidence of sudden death in the young and the proportion of diagnosed inherited cardiac diseases. Moreover, the additional value of the introduction of two different preventive strategies directed at early detection of inherited cardiac diseases in first-degree relatives to usual care will be evaluated. Conclusion. The CAREFUL study will help to set a new standard of care in the evaluation of young sudden death victims and their relatives to identify the presence of inherited cardiac diseases, in order to prevent sudden death. (Neth Heart J 2010;18:286-90.).

Founder mutations in hypertrophic cardiomyopathy patients in the Netherlands.

In this part of a series on cardiogenetic founder mutations in the Netherlands, we review the Dutch founder mutations in hypertrophic cardiomyopathy (HCM) patients. HCM is a common autosomal dominant genetic disease affecting at least one in 500 persons in the general population. Worldwide, most mutations in HCM patients are identified in genes encoding sarcomeric proteins, mainly in the myosin-binding protein C gene (MYBPC3, OMIM #600958) and the beta myosin heavy chain gene (MYH7, OMIM #160760). In the Netherlands, the great majority of mutations occur in the MYBPC3, involving mainly three Dutch founder mutations in the MYBPC3 gene, the c.2373_2374insG, the c.2864_2865delCT and the c.2827C>T mutation. In this review, we describe the genetics of HCM, the genotype-phenotype relation of Dutch founder MYBPC3 gene mutations, the prevalence and the geographic distribution of the Dutch founder mutations, and the consequences for genetic counselling and testing. (Neth Heart J 2010;18:248-54.).

Risk stratification for sudden cardiac death in hypertrophic cardiomyopathy: Dutch cardiologists and the care of mutation carriers.

Background. Patients with hypertrophic cardiomyopathy (HCM) and HCM mutation carriers are at risk of sudden cardiac death (SCD). Both groups should therefore be subject to regular cardiological testing - including risk stratification for SCD - according to international guidelines. We evaluated Dutch cardiologists' knowledge of and adherence to international guidelines on risk stratification and prevention of SCD in mutation carriers with and without manifest HCM.Methods. A questionnaire was sent to 1109 Dutch cardiologists (in training) containing case-based questions.Results. The response rate was 21%. Own general knowledge on HCM care was rated as insufficient by 63% of cardiologists. The percentage of correct answers (i.e. in agreement with international guidelines), on the case-based questions ranged from 37 to 96%, being lowest in cases with an unknown number of risk factors for SCD. A substantial portion of correct answers was based on the correct answer 'ask an expert opinion'. Significantly more correct answers were provided in cases with manifest HCM. There was little difference between the answers of cardiologists with different self-reported levels of knowledge, with different numbers of HCM patients in their practice or with different numbers of carriers without manifest HCM.Conclusion. Knowledge on risk stratification and preventive therapy was mediocre, and knowledge gaps exist, especially on HCM mutation carriers without manifest disease. Fortunately, experts are frequently asked for their opinion which might bring patient care to an adequate level. Hopefully, our results will stimulate cardiologists to follow developments in this field, thereby increasing quality of care for HCM patients and mutation carriers. (Neth Heart J 2009;17:464-9.).

[Genetic identification of patients and families with a long-QT syndrome: large regional differences in the result of 10 years]. / Genetische identificatie van patiënten en families met lange-QT-syndroom: grote regionale verschillen in de resultaten van 10 jaar.

OBJECTIVE: To determine the pattern of referral of Dutch patients with a long-QT syndrome (LQTS) on the basis of the postal codes of the LQTS probands from whom blood samples were submitted for DNA diagnostics. DESIGN: . Retrospective cohort study. METHOD: From the databases that are coupled to DNA diagnostics, all index patients were included for whom LQTS diagnostics had been requested during the period 1996-2005 at two clinical genetics centres (the University Medical Centre in Amsterdam and Maastricht University Hospital). The results were related to the postal code of the referred patient and corrected for the number of inhabitants of the region concerned. RESULTS: A total of 421 potential LQTS probands were included. Corrected for the numbers of inhabitants in the various postal codes, the number of referrals varied from 3 per million to 110 per million inhabitants. In view of the most recent estimated prevalence of LQTS (1:2000), this means that only 15% ofthe carriers of the LQTS mutation have so far been detected. CONCLUSION: There were large regional differences in the Netherlands in the requests for DNA diagnostics in patients with clinical LQTS. The overwhelming majority of the LQTS patients in the Netherlands have not yet been referred or identified. Expanding the available courses for general practitioners and cardiologists that are given by the staff of the cardiogenetic centres would seem to be indicated.

Cardiogenetic counselling in a non-university hospital.

BACKGROUND: Inherited heart disease is becoming a substantial part of everyday cardiology practice while genetic counselling still only takes place at university hospitals. In this study we review our seven-year experience with cardiogenetic counselling in a non-university hospital. METHODS: Retrospective analysis of patient records. RESULTS: A total number of 83 index patients were counselled. In 65 patients DNA tests were performed, resulting in 26 positive tests. In all patients with genotype confirmation of hereditary cardiovascular disease and in 32 families without a molecular diagnosis, family screening was advised. Out of 120 subsequently tested family members, 47 molecular genetic diagnoses were confirmed. CONCLUSION: Although the number of patients reviewed was small, our data show that cardiogenetic diseases are part of daily cardiology practice. We believe counselling should be performed in more general hospitals. This is an excellent opportunity for collaboration between university and nonuniversity hospitals, with immediate benefit for patients and their relatives. (Neth Heart J 2007;15:412-4.).

Preferences of cardiologists and clinical geneticists for the future organization of genetic care in hypertrophic cardiomyopathy: a survey.

In view of the increasing demands for genetic counselling and DNA diagnostics in cardiogenetics, the roles of cardiologists and clinical geneticists in the delivery of care need to be redefined. We investigated the preferences of both groups of professionals with regard to the future allocation of six cardiogenetic responsibilities in counselling and testing, using hypertrophic cardiomyopathy (HCM) as a prevalent model disease. In this cross-sectional survey, the participants were Dutch cardiologists (n = 643) and clinical geneticists (n = 60), all members of professional societies. Response rates were 33 and 82%, respectively. In both groups, the majority preferred to perform most of the tasks described above in collaboration. Informing HCM patients about the genetics of HCM and requesting DNA testing in symptomatic patients was viewed by 43 and 35% of cardiologists, respectively, as their sole responsibility, however, and 39 and 59% of clinical geneticists did not object to these views. Both groups felt that the task of discussing the consequences of HCM for offspring and that of discussing the results of DNA diagnostics should be shared or performed by clinical geneticists. Both groups considered co-ordination of family screening the sole responsibility of clinical geneticists. Opinions on who should request DNA diagnostics in asymptomatic relatives were divided: 86% of clinical geneticists considered it their exclusive responsibility, 10% of cardiologists believed that this task could be performed individually by either group and 30% preferred to collaborate. Most professionals said that they would appreciate education programmes and clinical guidelines. Both cardiologists and clinical geneticists prefer to share rather than divide most cardiogenetic responsibilities in caring for HCM patients. Consequently, capacity problems in both groups are to be expected. To safeguard current professional standards in genetic counselling and testing, deployment of non-medical personnel might be essential.

Can parents adjust to the idea that their child is at risk for a sudden death?: Psychological impact of risk for long QT syndrome.

Can a parent adjust to the idea that its child is at risk for a sudden death? This question is raised by a diagnostic procedure in which children were tested for an inherited Long QT Syndrome (LQTS). This potentially life-threatening but treatable cardiac arrhythmia syndrome may cause sudden death, especially in children and young adults. The long-term psychological effects are described for parents whose children were tested for inherited LQTS. The adverse short-term impact of such testing has been described previously. The goal of this investigation is to determine whether this distress endures. Thirty-six parents completed measures of psychological distress. With the twenty-four parents of carrier children, a semi-structured interview was held 18 months after DNA disclosure. Parents of carrier children reported more distress than parents of non-carrier children. Parents of carrier children remained vulnerable to high levels of distress; up to one-third of these parents showed clinically relevant high levels of distress. High levels of distress were reported by parents of carrier children who (1) were highly distressed at previous assessments, (2) were familiar with the disease for a longer time, (3) had experienced a sudden death in the family, (4) were lesser educated, and who (5) were unsatisfied with the given information. Parents were particularly concerned about possible hazardous behavior during puberty. We conclude that the continuous threat of developing LQTS symptoms despite prophylactic treatment affected the psychological well-being of the parents for a long time. In light of the tempetuous developments in the areas of cardiac genetics, periodical information on new insight and developments may act as a buffer for the parents' (growing) concerns about their child's inherited disorder.

[Sudden death at young age and the importance of molecular-pathologic investigation]. / Plotseling overlijden op jonge leeftijd en het belang van moleculair-pathologisch onderzoek.

The autopsy of a 16-year-old boy who had died suddenly revealed hypertrophic cardiomyopathy (HCM). Molecular genetic investigation revealed mutations in the MYBPC3 gene. His surviving family members could then be examined and reassured that they did not carry the mutation. An 18-year-old boy who died suddenly turned out to have known HCM. No further investigations were done and no tissue was saved. Genetic investigation of his immediate family was impossible due to the lack of a known mutation in the family. Periodic examination in clinically unaffected family members was therefore advised. Sudden cardiac death at young age is not infrequently the first symptom of an inherited cardiac disease. Because these diseases usually inherit as an autosomal dominant trait, first-degree family members have a 50% chance of carrying the same genetic defect. Besides clinical cardiologic examination of the remaining family members, post-mortem molecular genetic investigation can be of value in reaching a diagnosis and in determining the subsequent therapeutic options for immediate relatives.

High distress in parents whose children undergo predictive testing for long QT syndrome.

OBJECTIVES: To assess the psychological effect of predictive testing in parents of children at risk for long QT syndrome (LQTS) in a prospective study. METHODS: After their child was clinically screened by electrocardiography and blood was taken for DNA analysis, and shortly after delivery of the DNA test result, 36 parents completed measures of psychological distress. RESULTS: 24 parents were informed that at least one of their children is a mutation carrier. Up to 50% of the parents of carrier children showed clinically relevant high levels of distress. Parents who were familiar with the disease for a longer time, who had more experiences with the disease in their family and who received positive test results for all their children were most distressed. CONCLUSIONS: Predictive ECG testing together with DNA testing has a profound impact on parents whose minors undergo predictive testing for LQTS.

An extended family suddenly confronted with a life-threatening hereditary arrhythmia.

OBJECTIVE: This exploratory study serves to illustrate the psychological impact on an extended family in the process of genetic counselling and testing for a potentially life-threatening arrhythmia, the long-QT syndrome (LQTS). METHOD: All members of the third generation and their partners (n=11) were interviewed, the mutation carriers with partners twice. In addition they completed measures for anxiety and depression three times in 18 months. RESULTS: During the interviews these family members emphasised the damaged solidarity when the family is divided into carriers and noncarriers of a mutation in a LQTS predisposing gene. This demonstrates one way in which a family can react to the reality of being at risk of a potentially severe disease. Rewriting family history and mourning early death seem other ways to deal with this. The distress scores, especially of the women, were moderate to clinically high, not because of their own chance of having an arrhythmia but more due to their children's risk. CONCLUSION: Mothers need educational even more than emotional support, because the lifestyle of their carrier children is in need of radical change. The setting of a combined outpatient cardiogenetic clinic with a medical and psychosocial staff meets such needs efficiently.

Family and population strategies for screening and counselling of inherited cardiac arrhythmias.

Family screening in inherited cardiac arrhythmias has been performed in The Netherlands since 1996, when diagnostic DNA testing in long QT syndrome (LQTS) and hypertrophic cardiomyopathy (HCM) became technically possible. In multidisciplinary outpatient academic clinics, an adjusted protocol for genetic counselling, originally derived from predictive testing in Huntington's disease, is being used. 1110 individuals, including 842 relatives of index patients, were informed about their risks, and most were tested molecularly and/or clinically for carriership of the disease present in their family. Of 345 relatives who were referred for cardiologic follow-up, 189 are being treated, because of an increased risk of life-threatening arrhythmias. Evaluation of the psychological and social consequences of family screening for inherited arrhythmias can be performed by using the adapted criteria of Wilson and Jüngner, i.e., from a point of view of public health. Preliminary results of psychological research show that parents of children at risk for LQTS show high levels of distress. Many other aspects have to be evaluated yet, making final conclusions about the feasibility of family screening difficult, particularly in HCM. Clinical guidelines are urgently needed. Population screening by molecular testing, for instance in athletic preparticipation screening, will become possible in the future and has its own prerequisites for success.

Genetic knowledge and counselling skills of Dutch cardiologists: sufficient for the genomics era?

AIMS: Genetic scientific knowledge is growing rapidly but how this affects clinical practice is unclear. We investigated the levels of knowledge, practical skills and clinical genetic practices of Dutch cardiologists. METHODS AND RESULTS: A survey was designed to assess cardiologists' experience with genetic aspects of hypertrophic cardiomyopathy, self-reported genetic knowledge, and genetic skills in general and aimed at this disease. In addition, cardiologists' opinions on five possible measures for improvement were obtained. STUDY POPULATION: all Dutch cardiologists (n=643). Median number of patients suffering from hypertrophic cardiomyopathy per cardiologist is five. Forty-one percent of respondents do not give information about genetics to all their patients. Cardiologists rarely initiate DNA tests for hypertrophic cardiomyopathy. Only 38% refer patients to clinical geneticists. Self-reported knowledge levels are low (average score 3.3-5.1, 0-10 scale). Cardiologists with an established working relationship with a clinical geneticist report significantly higher levels of knowledge. Clinical guidelines, education and improved collaboration with clinical geneticists are preferred. CONCLUSION: Dutch cardiologists' genetic knowledge and clinical genetic practice levels are insufficient. As a result, clinical genetic care for patients with hypertrophic cardiomyopathy is poor. Improvements proposed include advancement of knowledge (education, professional guidelines) and structural measures (working relationships, multidisciplinary outpatient clinics). Collaboration of cardiologists and clinical geneticists is urgently needed to optimise cardiogenetic patient care.