Elevated levels of schizotypal features in parents of patients with a family history of schizophrenia spectrum disorders

There is some evidence that schizotypal traits are related to a genetic or familial liability to develop schizophrenia. However, it is unclear whether the number of schizotypal traits is elevated in parents of schizophrenia patients compared with controls. This study used the Schizotypal Personality Questionnaire to investigate the difference in number of schizotypal traits between both parents of 36 patients with schizophrenia (n = 72 persons) and 26 healthy married control couples (n = 52 persons). Parents of patients had a lower score on the positive dimension of schizotypy than healthy controls. There was no difference on the negative or disorganization dimension between groups. The difference on the positive dimension might have been caused by a difference in response style between parents of patients and controls due to the fact that parents are more familiar with schizophrenia than controls. Of interest, parents with a family history of schizophrenia spectrum disorders had more positive and negative schizotypal traits than parents without a family history of schizophrenia spectrum disorders. Because these two groups of parents differ in only genetic risk, not familiarity with schizophrenia, results suggest that the negative and positive dimension of schizotypy are related to a familial or genetic vulnerability to schizophrenia.