In order to know the higher truth of the condition be called sz,you must skip or completely ignore the course of all side bad effects (the characteristics of things you called it the symptoms of schizophrenia -except for the things called hallucinations !)
Because,the hallucinations is form both of the cause structure and functional cause of the condition you call it schizophrenia ,it is the substance and root origin of the whole condition that you call it SZ
Therefore,it is supposed that,you do not take the course of sz’s symptoms as an argument or/ identical aspects with the symptoms of any genetic disease or mental illness,and then incorrectly adhere to the assumption that these symptoms of sz are the product of a disease or illness ,because when you go to search for a genetic cause for the whole condition or its symptoms you will find nothing !
Just look very carefully at the thing called hallucination,know what is it ,then match that with the existential features of this thing as the person feels,perceives,coexists with and deal with it moment by moment all period time of wakefulness
After that ,you are free to ask;
Is there a human gene /genome that has creation properties that make it capable of creating the thing called hallucination ?
The most a gene can create is to make a copy of itself /make proteins
Could this or that create the hallucination ?
In reality,the hallucination is a living creature ,it is a free independent living parasitical psychological entity (s) …etc and it is not a mental symptom of any human disease