Schizophrenia in a 47,XYY male

A case of schizophrenia in a 47,XYY male diagnosed according to strict phenomenological criteria is presented. The authors suggest that the 47,XYY chromosome anomaly should be added to the list of possible causes of symptomatic schizophrenia, and express the hope that future investigations of the effects of an extra Y chromosome in brain function will yield clues as to the aetiology of idiopathic schizophrenia.