[Long QT-interval syndrome and investigation of heritability: psychological reactions in three generations in one family].

DNA diagnostics were carried out in a family after the long QT interval syndrome had been diagnosed in one of its members. The psychic reactions to this testing were different from those seen in other hereditary diseases such as Huntington's disease. This was probably due to the sudden and unexpected occurrence of the arrhythmia. The family members in whom clinical and DNA diagnostics gave purely negative findings were not relieved, owing to solidarity with the affected relatives. Their partners did not understand this response. The anxiety and concern of the gene carriers had nothing to do with their own health status but with that of their carrier children. These parents were in need of educational counselling and advice. The results of clinical and DNA diagnostics affected the family relationships: in carriers the feeling of closeness grew, while the non-carriers were afraid of loss of family closeness.