40+ years of the Huntington disease predictive genetic testing protocol: Recommendations for an update

Guidance for predictive genetic testing for Huntington disease (HD) has been available for more than four decades and has been applied to other adult-onset hereditary conditions, especially neurogenetic conditions. Yet this protocol has not been updated since 2016 even though there have been significant changes in healthcare delivery and policy/legal issues, including widespread use of telemedicine and new legislation impacting patients' ready access to medical records. There also have been technological advances where HD status can be revealed with genomic sequencing and societal paradigm shifts away from paternalism. Even with the well-established components and content to cover for predictive genetic testing for HD, variability exists in how the guidance has been applied by different institutions across the United States. This variability in clinical practice can be attributed to multiple factors including institutional differences in clinical staffing, whether genetic counselors are licensed, and approaches to care. This article describes the protocol's history and how the above changes affect aspects of this guidance. Given these changes and growing availability of predictive genetic testing, we recommend an update to the 2016 Huntington Disease Society of America's (HDSA) protocol, suggest changes and offer interim practice guidance. In summary, because of changes in technology, laws, and healthcare, the Huntington disease protocol for predictive genetic testing needs to be updated. This paper offers recommendations for these changes.