Cause of schizophrenia is multifactorial. It can run in families- 10% approx risk if you have one first degree relative with schizophrenia and increases with more relatives or identical twin with the same problem. Environmental factors like stress, use of alcohol or illicit substances like cannabis and stimulants potentials the risks of developing psychosis and schizophrenia.

There is no specific trait that can predict a patient can develop schizophrenia.. There are multiple aspects that can lead to it..