Psychiatric implications of presymptomatic testing for Huntington's disease.

Responses of 69 at-risk individuals suggest that potential for psychiatric problems exists for those testing positive for the Huntington Disease gene and for their relatives. Their families were found to have high rates of psychiatric dysfunctions and suicide. Poorly developed social support networks and the psychological defensive strategies of many at-risk people may also contribute to post-test psychiatric morbidity. The active involvement of mental health professionals is emphasized.