Issues concerning the evaluation and regulation of predictive genetic testing

Analysis of pre-test interviews in a cohort of Brazilian patients with movement disorders

Spinocerebellar ataxias and Huntington disease are heritable, adult onset, neurodegenerative disorders of movement. Both are autosomal dominant and caused by expansions in trinucleotide sequences in several genes. Because these expansions are associated with an almost complete penetrance, genetic tests are available at the diagnostic and predictive level. In this study, we describe the expectations and issues raised during pre-test interviews for genetic counselling for these diseases. Data from pre-test interviews with 97 patients and at-risk relatives for spinocerebellar ataxia (SCA) or Huntington disease was comprised of close-ended questions (demographics, personal and current disease history) and open-ended questions, where individuals were asked to describe their hopes and expectations on the genetic counselling evaluation and also their degree of knowledge about genetics and medical genetics. Amongst the main expectations identified in patients and at-risk relatives, issues related to the aetiological diagnosis and/or disclosure of the at-risk status were those most frequently mentioned (57 %). Improvement in quality of life was another identified issue (17 %). Interestingly, the issue of inheritance/transmission was identified as the main expectation by a minority of individuals (3 %). Pre-test interviews are valuable tools to identify issues raised by consultands and promote a better communication between the patient, family and the genetic counselling team.

Recommendations for returning genomic incidental findings? We need to talk!

The American College of Medical Genetics and Genomics recently issued recommendations for reporting incidental findings from clinical whole-genome sequencing and whole-exome sequencing. The recommendations call for evaluating a specific set of genes as part of all whole-genome sequencing/whole-exome sequencing and reporting all pathogenic variants irrespective of patient age. The genes are associated with highly penetrant disorders for which treatment or prevention is available. The effort to generate a list of genes with actionable findings is commendable, but the recommendations raise several concerns. They constitute a call for opportunistic screening, through intentional effort to identify pathogenic variants in specified genes unrelated to the clinical concern that prompted testing. Yet for most of the genes, we lack evidence about the predictive value of testing, genotype penetrance, spectrum of phenotypes, and efficacy of interventions in unselected populations. Furthermore, the recommendations do not allow patients to decline the additional findings, a position inconsistent with established norms. Finally, the recommendation to return adult-onset disease findings when children are tested is inconsistent with current professional consensus, including other policy statements of the American College of Medical Genetics and Genomics. Instead of premature practice recommendations, we call for robust dialogue among stakeholders to define a pathway to normatively sound, evidence-based guidelines.

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.