Subjects at Risk for Genetic Late-Onset Neurological Diseases: Objective Knowledge.

BACKGROUND/AIMS: This study addresses the objective knowledge about the disease of subjects at risk for 3 genetic late-onset neurological diseases (LOND): familial amyloid polyneuropathy (FAP) TTR V30M, Huntington disease (HD), and Machado-Joseph disease (MJD).

METHODS: Subjects at risk for FAP, HD, and MJD submitted to genetic counseling to know their status (carrier or non-carrier) and subjects at risk for hereditary hemochromatosis (HH), the control group, completed a sociodemographic questionnaire and answered the open-ended question: "What do you know about this disease?."

RESULTS: From 10 categories of answers, references to the disease, quantitative answers, references to the family, and metaphors stood out. References to the disease, references to the family, and metaphors were mentioned more often by subjects at risk for LOND than by subjects at risk for HH (control group).

CONCLUSION: The disease itself and its meaning as well as sick relatives play a key role in the objective knowledge about LOND. Thus, genetic counseling protocols of subjects at risk for LOND should include questions concerning family knowledge and disease experience.