The long-term effect of genetic testing for the diseases evaluated in our study (hereditary ataxias and neuromuscular disorders) is unknown.1 One of the objectives of our study was to begin a systematic investigation of this issue. Approximately one quarter to one third of the subjects in our study indicated feelings of anxiety several years after genetic testing, but the practical significance of this finding is unknown, the number of subjects was small, and the duration of follow-up was relatively short. The point of Figure 2 in our article was to demonstrate the wide variability and unpredictability of these responses in individual subjects. The follow-up response rates are representative of the total subject population and include 66% of those eligible at 1 year after testing and 62% at 2 years. Six subjects have now been studied for 5 years, and we hope to collect more extensive long-term data.
Smith CO, Lipe HP, Bird TD. Impact of Presymptomatic Genetic Testing for Hereditary Ataxia and Neuromuscular Disorders: Where is the Evidence?—Reply. Arch Neurol. 2005;62(1):164. doi:10.1001/archneur.62.1.164-b