POLYDACTYLY AND PSYCHOSIS 5 CASES OF COOCCURRENCE

Background Abnormalities presumed to occur during foetal life have bee n associated with schizophrenia. Polydactyly is a developmental abnorm ality but no previous association has been reported between polydactyl y and functional psychotic illness. Method individuals with both polyd actyly and a functional psychosis were ascertained during a study of f amilial schizophrenia. Results Five such individuals were ascertained in the course of assessing 234 individuals with familial psychosis, gi ving a rate of polydactyly in the sample of around 10 times the genera l population rate. Conclusions This study provides preliminary evidenc e that polydactyly is over-represented in individuals with familial sc hizophrenia and related psychotic illnesses.