Our study on long-term outcome of presymptomatic testing for Huntington disease had two aims: the comparison of the psychological well-being and social adjustment of carriers and non-carriers of the mutation, and the identification of psychological determinants to improve care/support of testees. We performed a cross-sectional study of 351 persons who underwent presymptomatic testing. Those who had motor signs were excluded from the comparison of asymptomatic carrier and non-carriers. A structured interview including five self-report scales and the MINI (Mini International Neuropsychiatric Inventory) was proposed to detect a psychopathology or problem with social adjustment.