Topic 11.6. Optimal genetic support services for individuals with Friedreich ataxia and their families
This chapter of the Clinical Management Guidelines for Friedreich Ataxia and the recommendations and best practice statements contained herein were endorsed by the authors and the Friedreich Ataxia Guidelines Panel in 2022.
Topic Contents
11.6 Optimal genetic support services for individuals with Friedreich ataxia and their families
Disclaimer / Intended Use / Funding
Disclaimer
The Clinical Management Guidelines for Friedreich ataxia (‘Guidelines’) are protected by copyright owned by the authors who contributed to their development or said authors’ assignees.
These Guidelines are systematically developed evidence statements incorporating data from a comprehensive literature review of the most recent studies available (up to the Guidelines submission date) and reviewed according to the Grading of Recommendations, Assessment Development and Evaluations (GRADE) framework © The Grade Working Group.
Guidelines users must seek out the most recent information that might supersede the diagnostic and treatment recommendations contained within these Guidelines and consider local variations in clinical settings, funding and resources that may impact on the implementation of the recommendations set out in these Guidelines.
The authors of these Guidelines disclaim all liability for the accuracy or completeness of the Guidelines, and disclaim all warranties, express or implied to their incorrect use.
Intended Use
These Guidelines are made available as general information only and do not constitute medical advice. These Guidelines are intended to assist qualified healthcare professionals make informed treatment decisions about the care of individuals with Friedreich ataxia. They are not intended as a sole source of guidance in managing issues related to Friedreich ataxia. Rather, they are designed to assist clinicians by providing an evidence-based framework for decision-making.
These Guidelines are not intended to replace clinical judgment and other approaches to diagnosing and managing problems associated with Friedreich ataxia which may be appropriate in specific circumstances. Ultimately, healthcare professionals must make their own treatment decisions on a case-by-case basis, after consultation with their patients, using their clinical judgment, knowledge and expertise.
Guidelines users must not edit or modify the Guidelines in any way – including removing any branding, acknowledgement, authorship or copyright notice.
Funding
The authors of this document gratefully acknowledge the support of the Friedreich Ataxia Research Alliance (FARA). The views and opinions expressed in the Guidelines are solely those of the authors and do not necessarily reflect the official policy or position of FARA.
11.6 Optimal genetic support services for individuals with Friedreich ataxia and their families
Martin B. Delatycki, Alexandra Durr, Paola Giunti, Grace Yoon and Susan E. Walther
As there are no specific clinical studies to inform the practice of genetic counseling in relation to FRDA, these guidelines are based on standard genetic counseling practice and the consensus of the expert authors of this chapter.
When an individual is diagnosed with FRDA, referral to a clinical geneticist or genetic counselor should be considered and the following issues should be discussed:
● Autosomal recessive inheritance and the genetic mechanism of FRDA.
● The implications for other family members, including:
○ 1-in-4 risk of FRDA in siblings (existing and future)
○ risk of FRDA for the offspring of the affected individual (generally relevant to older teenagers and adults)
○ carrier risk and availability of testing for relatives
○ availability of reproductive options where both members of a couple are identified as carriers.
The benefits of accurate genetic counseling include informed decision-making about testing for carrier status and reproductive options. It can also assist families in making decisions about testing for asymptomatic minors. The process can be of psychosocial benefit in dealing with the impact of being diagnosed (or a child being diagnosed) with FRDA.
The process of genetic counseling can also assist with managing the potential harms associated with genetic testing for affected or carrier status. Identifying that an asymptomatic individual will develop symptoms of FRDA through a genetic test may cause significant psychological morbidity, particularly if the individual was having testing to define carrier status and thus was not psychologically prepared for such an outcome. Identifying an individual as a carrier may cause short-term psychological morbidity, although studies of testing in other conditions show that being found to be a carrier rarely has major psychological impacts, particularly if that person’s partner is found to not be a carrier.
The services required to ensure high quality genetic diagnosis and counseling include a clinical genetics service and access to laboratory testing for the FXN GAA repeat and FXN point mutations/deletions.
All individuals identified pre-symptomatically and their families would benefit from immediate post-test counseling and psychosocial support and referral for appropriate neurological and cardiac surveillance.
There is no evidence to support routine use of any pharmacological therapies in patients diagnosed with Friedreich ataxia pre-symptomatically.
Martin B. Delatycki, MBBS, FRACP, PhD
Co-Director, Bruce Lefroy Centre, Murdoch Children’s Research Institute, Parkville, Victoria, Australia Email: martin.delatycki@vcgs.org.au
Alexandra Durr, MD, PhD
Professor of Neurogenetics, Sorbonne Université, Paris, France
Email: alexandra.durr@icm-institute.org
Paola Giunti, MD, PhD
Professor, Queen Square Institute of Neurology, UCL, London, UK
Email: p.giunti@ucl.ac.uk
Susan E. Walther, MS, CGC
Genetic Counselor, Clinic for Special Children, Strasburg, Pennsylvania, USA
Grace Yoon, MD
Clinical Geneticist, The Hospital for Sick Children, Toronto, Ontario, Canada
Email: grace.yoon@utoronto.ca
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These Guidelines are systematically developed evidence statements incorporating data from a comprehensive literature review of the most recent studies available (up to the Guidelines submission date) and reviewed according to the Grading of Recommendations, Assessment Development and Evaluations (GRADE) framework © The Grade Working Group.
This chapter of the Clinical Management Guidelines for Friedreich Ataxia and the recommendations and best practice statements contained herein were endorsed by the authors and the Friedreich Ataxia Guidelines Panel in 2022.
It is our expectation that going forward individual topics can be updated in real-time in response to new evidence versus a re-evaluation and update of all topics simultaneously.