[Predictive testing: presymptomatic diagnosis in neurogenetic disorders].

Area of Science:

• Neurogenetics
• Neurodegenerative Disorders
• Predictive Genetic Testing

Context:

• Presymptomatic genetic testing is available for Huntington disease and other neurogenetic disorders.
• The absence of preventive/curative treatments complicates predictive testing decisions.
• Carrier status does not predict disease onset or progression, impacting future planning.

Purpose:

• To explore the implications of presymptomatic genetic testing for various neurogenetic disorders.
• To highlight the importance of a multidisciplinary approach in predictive testing.
• To analyze motivations and outcomes of predictive testing, including prenatal testing requests.

Summary:

• A minority of at-risk individuals pursue presymptomatic testing, with nearly 50% not completing the process.
• Unfavorable test results often carry more significant negative consequences than favorable ones.
• Multidisciplinary care and adequate decision-making time are beneficial, as seen in Huntington disease and spinocerebellar ataxias.

Impact:

• Limited experience exists for familial Alzheimer's and Creutzfeldt-Jakob diseases due to dementia presence.
• Further research is needed for disorders like autosomal dominant spastic paraplegias, which typically don't reduce life expectancy.
• The landscape of predictive testing may significantly change with the advent of effective treatments.