Neurodevelopmental indices and the development of psychotic symptoms in subjects at high risk of schizophrenia

Background Neurological 'soft signs' and minor physical anomalies (MPAs) ar e reported to be more frequent in patients with schizophrenia than in contr ols. Aims To determine whether these disturbances are genetically mediated, and whether they are central to the genesis of symptoms or epiphenomena, Method We obtained ratings in 152 individuals who were antipsychotic drug-f ree and at high risk. some of whom had experienced psychotic symptoms, as w ell as 30 first-episode patients and 35 healthy subjects. Results MPAs and Neurological Evaluation Scale (NES) 'sensory integration a bnormalities' were more frequent in high-risk subjects than in healthy cont rols. but there were no reliable differences between high-risk subjects wit h and without psychotic Symptoms. MPAs were most frequent in high-risk subj ects with least genetic liability and NES scores showed no genetic associat ions. Conclusions The lack of associations with psychotic symptoms and genetic li ability to schizophrenia suggests that soft signs and physical anomalies ar e nonspecific markers of developmental deviance that are not mediated by th e gene(s) for schizophrenia. Declaration of interest None. Funding from the Medical Research Council of Great Britain.