The answer to this question is complicated by the fact that schizophrenia is a group of diseases whose etiology is still unknown, and although it has been developing for a century, it is still relatively complex. It can be divided into the following causes. These causes are often intertwined and affect the onset of the patient. Because people are a composite of their congenital and acquired environment, all mental illnesses are naturally related to this. Genetic factors: Clinical genetic studies have proven that genetic factors play a role in the development of this disease. Domestic and international family surveys on schizophrenia have found that the prevalence rate among close relatives of patients with this disease is several times higher than that of the general population, and the closer the blood relationship, the higher the prevalence rate. Studies on twins foretell that the prevalence of monozygotic twins is four to six times higher than that of dizygotic twins. Foster child studies have found that children born to schizophrenic mothers who grew up in foster care and lived in a normal family environment still have a higher prevalence in adulthood, suggesting a major role of genetic factors in the development of the disease. Genetic loci associated with schizophrenia have been identified on chromosomes 5 and 11, and no specific genetic mutations have been found.