This study examined the first participants who registered for the Huntington's disease predictive testing program 1990-1995 in Stockholm, Sweden. A psychosocial investigation was performed to evaluate potential effects of the presymptomatic testing. The results showed no significant differences between 13 gene carriers and 21 noncarriers in pretest attitudes, expectations, general well-being, life satisfaction and lifestyle, the need for support, estimated sense of wellbeing or degree of health. However, both groups showed high suicidal ideation and self-injurious behavior. Noncarriers had a very high frequency of attempted suicide, and both groups had similarly pronounced psychiatric dysfunction. Their relatives also had high frequencies of psychiatric diseases, suicide or suicidal attempts. Most of the participants had a desire to meet a psychologist or a social worker. The need for counseling, using a well designed protocol, and the importance of focusing on suicide risk of participants in predictive testing programs is emphasized.