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Aims: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare genetic condition caused predominantly by mutations within desmosomal genes. The mutation leading to ARVC-5 was recently identified on the island of Newfoundland and caused by the fully penetrant missense mutation p.S358L in TMEM43. Although TMEM43-p.S358L mutation carriers were also found in the USA, Germany, and Denmark, the genetic relationship between North American and European patients and the disease mechanism of this mutation remained to be clarified., Methods and Results: We screened 22 unrelated ARVC patients without mutations in desmosomal genes and identified the TMEM43-p.S358L mutation in a German ARVC family. We excluded TMEM43-p.S358L in 22 unrelated patients with dilated cardiomyopathy. The German family shares a common haplotype with those from Newfoundland, USA, and Denmark, suggesting that the mutation originated from a common founder. Examination of 40 control chromosomes revealed an estimated age of 1300-1500 years for the mutation, which proves the European origin of the Newfoundland mutation. Skin fibroblasts from a female and two male mutation carriers were analysed in cell culture using atomic force microscopy and revealed that the cell nuclei exhibit an increased stiffness compared with TMEM43 wild-type controls., Conclusion: The German family is not affected by a de novo TMEM43 mutation. It is therefore expected that an unknown number of European families may be affected by the TMEM43-p.S358L founder mutation. Due to its deleterious clinical phenotype, this mutation should be checked in any case of ARVC-related genotyping. It appears that the increased stiffness of the cell nucleus might be related to the massive loss of cardiomyocytes, which is typically found in ventricles of ARVC hearts., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Objective: To provide a legal and ethical analysis of some of the implementation challenges faced by the Population Therapeutics Research Group (PTRG) at Memorial University (Canada), in using genealogical information offered by individuals for its genetics research database., Materials and Methods: This paper describes the unique historical and genetic characteristics of the Newfoundland and Labrador founder population, which gave rise to the opportunity for PTRG to build the Newfoundland Genealogy Database containing digitized records of all pre-confederation (1949) census records of the Newfoundland founder population. In addition to building the database, PTRG has developed the Heritability Analytics Infrastructure, a data management structure that stores genotype, phenotype, and pedigree information in a single database, and custom linkage software (KINNECT) to perform pedigree linkages on the genealogy database., Discussion: A newly adopted legal regimen in Newfoundland and Labrador is discussed. It incorporates health privacy legislation with a unique research ethics statute governing the composition and activities of research ethics boards and, for the first time in Canada, elevating the status of national research ethics guidelines into law. The discussion looks at this integration of legal and ethical principles which provides a flexible and seamless framework for balancing the privacy rights and welfare interests of individuals, families, and larger societies in the creation and use of research data infrastructures as public goods., Conclusion: The complementary legal and ethical frameworks that now coexist in Newfoundland and Labrador provide the legislative authority, ethical legitimacy, and practical flexibility needed to find a workable balance between privacy interests and public goods. Such an approach may also be instructive for other jurisdictions as they seek to construct and use biobanks and related research platforms for genetic research.

Our group previously described and mapped to chromosomal region 12p13 a form of dominantly inherited hereditary spastic ataxia (HSA) in three large Newfoundland (Canada) families. This report identifies vesicle-associated membrane protein 1 (VAMP1), which encodes a critical protein for synaptic exocytosis, as the responsible gene. In total, 50 affected individuals from these families and three independent probands from Ontario (Canada) share the disease phenotype together with a disruptive VAMP1 mutation that affects a critical donor site for the splicing of VAMP1 isoforms. This mutation leads to the loss of the only VAMP1 isoform (VAMP1A) expressed in the nervous system, thus highlighting an association between the well-studied VAMP1 and a neurological disorder. Given the variable phenotype seen in the affected individuals examined here, we believe that VAMP1 should be tested for mutations in patients with either ataxia or spastic paraplegia., (Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

In this clinical column, we discuss the ambiguous distinction between genetic research and clinical genetics, particularly for Mendelian diseases with high recurrence risk, high morbidity and/or mortality and the possible amelioration of such diseases by screening or treatment. We use arrhythmogenic right ventricular cardiomyopathy as an example of a lethal Mendelian disorder, which prompted the discussion contained in this column. Working with such diseases may mean that genetic researchers have some responsibility for both immediate research subjects and their extended families, as they obtain molecular genetic information. For some diseases, therefore, a willingness to accept genetic research results should be an inclusion criterion, and it may be considered unethical for research ethics boards to approve genetic studies unless measures to ensure clinical follow-up have been established. We recommend managing the tensions between genetic research and clinical practice by using disease-based genetic registers, organized within a clinical genetic service.

Arrhythmogenic right ventricular cardiomyopathy, a lethal autosomal dominant cause of sudden cardiac death in young people, is prevalent in Newfoundland and Labrador (genetic subtype ARVD5). In the absence of implantable cardioverter defibrillator treatment, death rates are extremely high. Research into arrhythmogenic right ventricular cardiomyopathy (ARVD5) began in the 1980s and the causative gene and mutation were discovered in 2008. The decades of research highlighted major issues associated with the ethical management of genetic information and the translation of research findings to clinical care. We describe these issues and the strategies used in managing them. Effective knowledge transfer of the research information has resulted in systematic clinical and genetic screening coupled with genetic counseling and treatment for at-risk family members. Improved survival for patients has been one clear result of this strategy. Optimal care of families where individuals are at-high risk of inheriting a disease with high morbidity and mortality requires the full integration of both genetic research and clinical genetics programs. Although yet to be fully effected in our setting, our discussion highlights both the ethical necessity as well as some practical barriers in realizing this outcome.

Despite a rapidly expanding literature on the issue of duty to warn at-risk relatives in the context of clinical genetic testing, little has been written on parallel issues with regard to the management of genetic research results. Some might view this lack as an indication that there is little to discuss in this regard. That is, standard practice is that data obtained through medical research should not be treated as though they are clinically relevant, and this standard should hold for genetic research as well. This paper challenges this conclusion and its underlying assumptions. We argue that the line between genetic research and clinical practice is often ambiguous. In some cases, research data gathered from a very small number of subjects could have immediate clinical implications. Hence, it is unethical for genetic researchers to absolve themselves of clinical responsibilities for research subjects and/or their families, on the grounds that the data were obtained for research purposes. Indeed, we argue that it could well be unethical to embark on some forms of genetic research unless advance arrangements have been made for genetic counseling and clinical follow-up. Furthermore, in some cases, it might be unethical to enroll subjects in studies if the subjects are unwilling to receive their individual results.