Genetic counseling issues in predictive genetic testing for familial adult-onset neurologic diseases

Prenatal Diagnostic Testing for Adult-Onset Neurodegenerative Disease

OBJECTIVE

This study investigated existing practices and institutional guidelines on prenatal diagnostic testing (PND) for adult-onset neurodegenerative disease (AOND) to identify points of consensus, disparities, and areas of need in healthcare settings across the United States (US) to better understand if national guidelines are needed.

METHODS

A questionnaire about institutional practices and guidelines on PND for AOND was distributed through the National Society of Genetic Counselors, Society for Maternal-Fetal Medicine, and Huntington's Disease Society of America Centers of Excellence. Of 104 responses, 50 met eligibility criteria and were analyzed for commonalities and shared themes.

RESULTS

Of those who provided responses, 80% reported that their institution does not have a formal protocol or written guidelines on PND for AOND. Challenges to PND for AOND included ethical decision making after a positive genetic result, double disclosure of fetal and parental status, and differing values among relevant stakeholders. Of those who provided responses, 100% indicated that national guidelines would be beneficial.

CONCLUSION

This study helps establish the need for national guidelines on PND for AOND given that most institutions surveyed do not have standardized protocols. Points of consensus and shared areas of uncertainty may serve as starting points for the formation of national practice guidelines.

Genetic counseling and testing for Huntington's disease: A historical review

This manuscript describes the ways in which genetic counseling has evolved since John Pearson and Sheldon Reed first promoted "a genetic education" in the 1950s as a voluntary, non-directive clinical tool for permitting individual decision making. It reviews how the emergence of Huntington's disease (HD) registries and patient support organizations, genetic testing, and the discovery of a disease-causing CAG repeat expansion changed the contours of genetic counseling for families with HD. It also reviews the guidelines, outcomes, ethical and laboratory challenges, and uptake of predictive, prenatal, and preimplantation testing, and it casts a vision for how clinicians can better make use of genetic counseling to reach a broader pool of families that may be affected by HD and to ensure that genetic counseling is associated with the best levels of care. © 2016 Wiley Periodicals, Inc.

Next-generation sequencing in the clinic: are we ready?

We are entering an era in which the cost of clinical whole-genome and targeted sequencing tests is no longer prohibitive to their application. However, currently the infrastructure is not in place to support both the patient and the physicians that encounter the resultant data. Here, we ask five experts to give their opinions on whether clinical data should be treated differently from other medical data, given the potential use of these tests, and on the areas that must be developed to improve patient outcome.

Genetic counselors' perceived responsibilities regarding reproductive issues for patients at risk for Huntington disease

Research indicates that health care professionals' attitudes may affect patients' decisions regarding prenatal Huntington Disease testing, but few studies have sampled genetic counselors. In this qualitative study, genetic counselors described their experiences counseling individuals at risk for HD regarding reproductive decision-making. Five major research questions were investigated: 1) What are genetic counselor responsibilities? 2) What issues arise for patients and counselors? 3) How do counselors reconcile prenatal testing with presymptomatic testing? 4) To what extent are counselors' initial expectations of at-risk patients' beliefs and behaviors met? and 5) What advice would counselors offer to novice practitioners about working with this patient population? Fifteen genetic counselors experienced in counseling individuals at risk for HD participated in a semi-structured phone interview that yielded several themes. For example, participants identified their primary responsibility as information provision; less prevalent were psychosocial support and facilitating decision making. The most common ethical challenge was testing prenatally for HD which also results in presymptomatic testing of minors. Participants were divided about how directive to be in response to this ethical issue and about termination of a gene positive pregnancy.

Familial screening and genetic counselling in hypertrophic cardiomyopathy: the Rotterdam experience

Hypertrophic cardiomyopathy (HCM) is a disease characterised by unexplained left ventricular hypertrophy (LVH) (i.e. LVH in the absence of another cardiac or systemic disease that could produce a similar degree of hypertrophy), electrical instability and sudden death (SD).Germline mutations in genes encoding for sarcomere proteins are found in more than half of the cases of unexplained LVH. The autosomal dominant inherited forms of HCM are characterised by incomplete penetrance and variability in clinical and echocardiographic features, prognosis and therapeutic modalities. The identification of the genetic defect in one of the HCM genes allows accurate presymptomatic detection of mutation carriers in a family. Cardiac evaluation of at-risk relatives enables early diagnosis and identification of those patients at high risk for SD, which can be the first manifestation of the disease in asymptomatic persons.In this article we present our experience with genetic testing and cardiac screening in our HCM population and give an overview of the current literature available on this subject. (Neth Heart J 2007;15:184-9.).

Dominant spinocerebellar ataxias: a molecular approach to classification, diagnosis, pathogenesis and the future

The capacity to use molecular techniques to establish the genetic diagnoses of the autosomal dominant ataxias has revolutionized the field. It is now possible to systematically classify these disorders according to the nature of the causative mutation, with implications for diagnostic testing, analysis of pathogenesis and therapeutic strategies. Here, the disorders are grouped into ataxias caused by CAG repeat expansions that encode polyglutamine, ataxias caused by mutations in ion channels, ataxias caused by repeat expansions that do not encode polyglutamine, and ataxias caused by point mutations. The clinical, pathological, genetic and pathogenic features of each disorder are considered and the current status and future of diagnosis and therapy are reviewed in light of this classification scheme.